• The human myristoylated alanine-rich C kinase substrate (MARCKS) gene (MACS). Analysis of its gene product, promoter, and chromosomal localization.

      Harlan, D M; Graff, J M; Stumpo, D J; Eddy, R L; Shows, T B; Boyle, John M; Blackshear, P J; Howard Hughes Medical Institute Laboratories, Duke University Medical Center, Durham, North Carolina 27710. (1991-08-05)
      The expression of a major cellular substrate for protein kinase C, the MARCKS protein, is regulated in a cell-, tissue-, and developmental stage-specific fashion; in addition, this expression can be stimulated acutely by various cytokines in certain cell types. We have begun to characterize the human gene in order to elucidate the genetic elements responsible for this highly regulated expression. We first cloned a human MARCKS cDNA, which encoded a predicted protein of 332 amino acids (Mr 31,600) that was approximately 89, 74, and 59% identical to the bovine, mouse, and chicken proteins, respectively. Regions conserved at the amino acid level included the amino-terminal myristoylation consensus sequence, the site of intron splicing, and the phosphorylation site domain. The human cDNA was used to demonstrate that tumor necrosis factor-alpha could rapidly stimulate MARCKS gene transcription in the human promyelocytic leukemia cell line HL60. Genomic clones were then isolated; sequence analysis identified a putative promoter region that had no TATA box and contained multiple transcription initiation sites in a region spanning 57 base pairs (bp). This was followed by a 5'-untranslated region of approximately 400 bp, which displayed a complex predicted secondary structure with a delta G of -73.4 kcal/mol. Plasmid constructions containing between 52 and 1453 bp of the human MARCKS promoter linked to the human growth hormone gene were then used in transient expression experiments. Constructions containing 52 and 110 bp of the MARCKS promoter did not exhibit promoter function while the larger constructions all exhibited promotor function; the 248-bp fragment of the MARCKS promoter was 80% as effective as the human ferritin promoter in stimulating expression of human growth hormone in intact cells. Using an insert from the human genomic clone as a probe, we identified human chromosome 6, q21-qter, as the location of the MARCKS gene; this has been assigned the gene symbol MACS.
    • The human papillomavirus (HPV) 16 E2 protein induces apoptosis in the absence of other HPV proteins and via a p53-dependent pathway.

      Webster, Kenneth; Parish, Joanna L; Pandya, Maya; Stern, Peter L; Clarke, Anthony R; Gaston, Kevin; Department of Biochemistry, School of Medical Sciences, University of Bristol, Bristol BS8 1TD, United Kingdom. (2000-01-07)
      The human papillomavirus (HPV) E2 protein regulates viral gene expression and is also required for viral replication. HPV-transformed cells often contain chromosomally integrated copies of the HPV genome in which the viral E2 gene is disrupted. We have shown previously that re-expression of the HPV 16 E2 protein in HPV 16-transformed cells results in cell death via apoptosis. Here we show that the HPV 16 E2 protein can induce apoptosis in both HPV-transformed and non-HPV-transformed cell lines. E2-induced apoptosis is abrogated by a trans-dominant negative mutant of p53 or by overexpression of the HPV 16 E6 protein, but is increased by overexpression of wild-type p53. We show that mutations that block the DNA binding activity of E2 do not impair the ability of this protein to induce apoptosis. In contrast, removal of both N-terminal domains from the E2 dimer completely blocks E2-induced cell death. Heterodimers formed between wild-type E2 and N-terminally deleted E2 proteins also fail to induce cell death. Our data suggest that neither the DNA binding activity of E2 nor other HPV proteins are required for the induction of apoptosis by E2 and that E2-induced cell death occurs via a p53-dependent pathway.
    • Human papillomavirus E7 induces p63 expression to modulate DNA damage response.

      Eldakhakhny, Sahar; Zhou, Qing; Crosbie, Emma J; Sayan, Berna S; Division of Cancer Sciences, School of Medical Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester Cancer Research Centre, Wilmslow Road, Manchester, M20 4QL, UK (2018-01-26)
      Cervical cancer is the third most common malignancy diagnosed in women worldwide. The major aetiological factor underlying the malignant transformation of cervical cells is the persistent infection with high-risk human papillomaviruses (HR-HPV), with more than 99% of cases expressing viral sequences. Here, we report a previously unknown mechanism driven by high-risk human papillomavirus E7 protein to modulate response to DNA damage in cervical cancer cells. Our data shows that HR-HPV E7 oncoprotein induces the transcription of the p53-family member p63, which modulates DNA damage response pathways, to facilitate repair of DNA damage. Based on our findings, we proposed a model, where HR-HPV could interfere with the sensitivity of transformed cells to radiation therapy by modulating DNA damage repair efficiency. Importantly, we have shown for the first time a critical role for p63 in response to DNA damage in cervical cancer cells.
    • Human papillomavirus infection of the uterine cervix of women without cytological signs of neoplasia.

      Toon, P; Arrand, John R; Wilson, Lynne P; Sharp, D; Department of Obstetrics and Gynaecology, North Manchester General Hospital, Manchester M8 6RB (1986-11-15)
      One hundred and six patients were studied whose cervical smears showed only non-specific inflammatory changes. Screening for genital pathogens yielded only a few positive cases. Histological examination of biopsy specimens taken by colposcopically directed tissue sampling showed cervical intraepithelial neoplasia in 13 of the women (12.3%). Deoxyribonucleic acid (DNA) hybridisation techniques were used to detect human papillomavirus, which was found in 24 patients (22.6%). In a second group of 104 patients with normal cervical cytology tissue biopsy samples were obtained and examined histologically but in no case was cervical intraepithelial neoplasia found. On DNA hybridisation, however, 12 patients (11.5%) were found to be positive for human papillomavirus. In this group finding human papillomavirus DNA was usually associated with a columnar ectopy. An association between human papillomavirus type 16 DNA and both cervical intraepithelial neoplasia and cervical cancer is well established. In this study it was type 16 which occurred most frequently in both groups.
    • Human papillomavirus type 16 E2- and L1-specific serological and T-cell responses in women with vulval intraepithelial neoplasia.

      Davidson, Emma J; Sehr, Peter; Faulkner, Rebecca L; Parish, Joanna L; Gaston, Kevin; Moore, Richard A; Pawlita, Michael; Kitchener, Henry C; Stern, Peter L; Immunology Group, Paterson Institute for Cancer Research, Christie Hospital NHS Trust, Wilmslow Road, Manchester M20 4BX, UK. (2003-08)
      Human papillomavirus type 16 (HPV-16)-associated vulval intraepithelial neoplasia (VIN) is frequently a chronic, multifocal high-grade condition with an appreciable risk of progression to vulval cancer. The requirement to treat women with VIN has recently stimulated the use of immunotherapy with E6/E7 oncogene vaccines. Animal models have shown that E2 may also be a useful vaccine target for HPV-associated disease; however, little is known about E2 immunity in humans. This study investigated the prevalence of HPV-16 E2-specific serological and T-cell responses in 18 women with HPV-16-associated VIN and 17 healthy volunteers. E2 responses were determined by full-length E2-GST ELISA with ELISPOT and proliferation assays using E2 C-terminal protein. As positive controls, HPV-16 L1 responses were measured using virus-like particles (VLPs) and L1-GST ELISA with ELISPOT and proliferation using VLPs as antigen. The VIN patients all showed a strong serological response to L1 compared with the healthy volunteers by VLP (15/18 vs 1/17, P<0.001) and L1-GST ELISA (18/18 vs 1/17, P<0.001). In contrast, L1-specific cellular immune responses were detected in a significant proportion of controls but were more prevalent in the VIN patients by proliferation assay (9/17 vs 17/18, P<0.02) and interferon-gamma ELISPOT (9/17 vs 13/18, P=not significant). Similar and low numbers of patients and controls were seropositive for E2-specific Ig (2/18 vs 1/17). In spite of previous studies showing the immunogenicity of E2 in eliciting primary T-cell responses in vitro, there was a low prevalence of E2 responses in the VIN patients and controls (2/18 vs 0/17).
    • Human papillomavirus type 16 E2-specific T-helper lymphocyte responses in patients with cervical intraepithelial neoplasia.

      Bontkes, Hetty J; De Gruijl, Tanja D; Bijl, Astrid; Verheijen, René H; Meijer, Chris J L M; Scheper, Rik J; Stern, Peter L; Burns, Julie E; Maitland, Norman J; Walboomers, Jan M; et al. (1999-09)
      T-cell-mediated immune responses against mucosal oncogenic types of human papillomaviruses (HPV) are thought to play a role in the control of the virus infection and its associated cervical lesions. The in vitro production of interleukin-2 by T-helper (Th) cells in response to the C-terminal and N-terminal domains of the HPV-16 E2 protein was determined in 74 women with cytological evidence of premalignant cervical epithelial neoplasia who participated in a non-intervention follow-up (FU) study. Cross-sectional analysis at the end of FU showed that Th cell responses against the C-terminal domain were associated with evidence of previous or present HPV-16 infection as compared to patients with no evidence of any HPV infection (18.9% versus 0%, P = 0.039). Th cell responses against the N-terminal domain were not associated with evidence of HPV-16 infection. No association with disease outcome was observed with Th cell responses against either of the E2 protein domains. However, longitudinal analysis revealed that Th cell responses against the C-terminal domain frequently occur at the time of virus clearance. Whether these responses are responsible for the clearance of the virus is not known.
    • Human papillomavirus type 16 E6 variants in cervical carcinoma: relationship to host genetic factors and clinical parameters.

      Brady, Claire S; Duggan-Keen, Margaret F; Davidson, Judith A; Varley, Jennifer; Stern, Peter L; Department of Immunology, Paterson Institute for Cancer Research, Christie Hospital NHS Trust, Wilmslow Road, Manchester M20 4BX, UK. (1999-12)
      Infection with human papillomavirus type 16 (HPV-16) confers a high risk for the development of cervical neoplasia. Variants of this virus may interact differentially with host genetic factors, possibly altering the disease course. Thus, HPV-16 E6 variants may differ in their ability to degrade p53 whereas the polymorphic p53 alleles may provide more or less susceptible substrates for the viral oncogene product. Also, E6 variants may differ in immunogenicity by generating different peptides for presentation by polymorphic HLA molecules to specific T cells. This study examines HPV-16 E6 sequence variation in cervical carcinomas from the UK and its relationship to polymorphism of HLA and p53 and to clinical parameters. Sequence analysis of the HPV-16 E6 ORF from 77 tumour biopsies detected the viral prototype sequence in 38% of cases. The most common variation detected was a T to G transition at base pair 350, resulting in an amino acid change from a leucine to a valine. Overall, the frequencies of 350T and 350G sequences were similar (49. 4% and 50.6% respectively). Other mutations of lower frequencies were detected together with and independently of 350G. HPV-16 E6 sequence variation at base pair 350 did not correlate with HLA genotype or clinical outcome. There was no difference in the distribution of p53 proline and arginine alleles between HPV-16-positive cervical carcinoma patients and local controls, and no influence on clinical outcome; however, there was a trend for an increased frequency of p53 arginine homozygotes among the 350T carcinoma patients.
    • Human papillomavirus type 16 E6/E7-specific cytotoxic T lymphocytes in women with cervical neoplasia.

      Bontkes, Hetty J; De Gruijl, Tanja D; Van den Muysenberg, Adrie J; Verheijen, René H; Stukart, Marij J; Meijer, Chris J L M; Scheper, Rik J; Stacey, Simon N; Duggan-Keen, Margaret F; Stern, Peter L; et al. (2000-10-01)
      Infection with oncogenic human papillomavirus (HPV) types is associated with the development of cervical neoplasia (CIN). The E6 and E7 oncoproteins are constitutively expressed in these lesions and are therefore putative targets for the immune response against HPV. The relation between HPV 16-specific memory cytotoxic T-cell precursor (mCTLp) activity to both oncoproteins and the natural course of cervical dysplasia was analyzed in 38 patients participating in a nonintervention cohort study of women with CIN and 11 HPV 16-positive cervical carcinoma patients. In a cross-sectional study at the end of follow-up prior to biopsy, 8 of 20 patients with a persistent HPV 16 infection had specific mCTLp against at least one of the two oncoproteins. By contrast, no specific mCTLp activity was detected in 11 HPV-negative patients or in 7 patients who had cleared an HPV 16 infection at the end of follow-up. However, 5 of 11 cervical carcinoma patients showed mCTLp activity against the E7 protein only. This study demonstrates that HPV 16 oncogene-specific mCTLp are present in women with HPV 16-positive CIN prior to any intervention. Since HPV-specific mCTLp were detected predominantly in women with high-grade lesions or invasive cervical carcinoma and not in women who cleared the virus, the role of naturally occurring mCTLp in the protection against HPV-associated cervical neoplasia remains to be established.
    • The human ROX gene: genomic structure and mutation analysis in human breast tumors.

      Lo Nigro, C; Venesio, T; Reymond, A; Meroni, G; Alberici, P; Cainarca, S; Enrico, F; Stack, Maria; Ledbetter, D H; Liscia, D S; et al. (1998-04-15)
      We have recently isolated a human gene, ROX, encoding a new member of the basic helix-loop-helix leucine zipper protein family. ROX is capable of heterodimerizing with Max and acts as a transcriptional repressor in an E-box-driven reporter gene system, while it was found to activate transcription in HeLa cells. ROX expression levels vary during the cell cycle, being down-regulated in proliferating cells. These biological properties of ROX suggest a possible involvement of this gene in cell proliferation and differentiation. The ROX gene maps to chromosome 17p13.3, a region frequently deleted in human malignancies. Here we report the genomic structure of the human ROX gene, which is composed of six exons and spans a genomic region of less than 40 kb. In an attempt to identify possible inactivating mutations in the ROX gene in human breast cancer, we performed a single-strand conformation polymorphism analysis of its coding region in 16 sporadic breast carcinomas showing loss of heterozygosity in the 17p13.3 region. No mutations were found in this analysis. Five nucleotide polymorphisms were identified in the ROX gene, three of which caused an amino acid substitution. These nucleotide changes were present in the peripheral blood DNAs of both the patients and the control individuals. In vitro translated assays did not show a significant decrease in the ability of the ROX mutant proteins to bind DNA or to repress transcription of a driven reporter gene in HEK293 cells. Despite experimental evidence that ROX might act as a tumor suppressor gene, our data suggest that mutations in the coding region of ROX are uncommon in human breast tumorigenesis.
    • Human spermbots for patient-representative 3D ovarian cancer cell treatment

      Xu, H.; Medina-Sánchez, M.; Zhang, W.; Seaton, Melanie; Brison, D. R.; Edmondson, R. J.; Taylor, Stephen S; Nelson, Louisa; Zeng, K.; Bagley, Steven; et al. (2020)
      Cellular micromotors are attractive for locally delivering high concentrations of drug, and targeting hard-to-reach disease sites such as cervical cancer and early ovarian cancer lesions by non-invasive means. Spermatozoa are highly efficient micromotors perfectly adapted to traveling up the female reproductive system. Indeed, bovine sperm-based micromotors have shown potential to carry drugs toward gynecological cancers. However, due to major differences in the molecular make-up of bovine and human sperm, a key translational bottleneck for bringing this technology closer to the clinic is to transfer this concept to human material. Here, we successfully load human sperm with Doxorubicin (DOX) and perform treatment of 3D cervical cancer and patient-representative ovarian cancer cell cultures, resulting in strong anticancer cell effects. Additionally, we define the subcellular localization of the chemotherapeutic drug within human sperm, using high-resolution optical microscopy. We also assess drug effects on sperm motility and viability over time, employing sperm samples from healthy donors as well as assisted reproduction patients. Finally, we demonstrate guidance and release of human drug-loaded sperm onto cancer tissues using magnetic microcaps, and show the sperm microcap loaded with a second anticancer drug, camptothecin (CPT), which unlike DOX is not suitable for directly loading into sperm due to its hydrophobic nature. This co-drug delivery approach opens up novel targeted combinatorial drug therapies for future applications.
    • Human T cell responses to HPV 16 E2 generated with monocyte-derived dendritic cells.

      Davidson, Emma J; Brown, Michael D; Burt, Deborah J; Parish, Joanna L; Gaston, Kevin; Kitchener, Henry C; Stacey, Simon N; Stern, Peter L; CRC Immunology Group, Paterson Institute for Cancer Research, Christie Hospital NHS Trust, Manchester, United Kingdom. (2001-12-15)
      Persistent infection with human papillomavirus (HPV) type 16 has been implicated in the etiology of cervical cancer. The E2 protein is required early in viral infection and therefore may serve as a useful immune target for a vaccine aimed at prevention or therapy of premalignant lesions. Dendritic cells (DC) prepared from monocytes and pulsed with bacterially produced HPV 16 E2 C-terminus protein were used to stimulate autologous T cells over several rounds of stimulation. T cells were tested for gamma-interferon release by ELISPOT and for cytotoxic activity by (51)chromium release assays. To generate E2-expressing target cells for cytotoxicity assays, we constructed a recombinant vaccinia virus encoding HPV 16 E2, which was used to infect autologous Epstein-Barr virus-transformed lymphoblastoid cell lines (LCL). The results show that DC pulsed with E2 C-terminus protein induce gamma-interferon-releasing T cells as demonstrated by ELISPOT. Furthermore, we demonstrate E2-specific lysis of vaccinia-E2 infected autologous LCL by CD8+ cytotoxic T lymphocytes (CTL). E2-specific CTL did not lyse untreated autologous LCL or LCL infected with wild-type vaccinia and showed low levels of cytotoxicity against natural killer cell-sensitive K562 cells. In addition, T cells stimulated with DC in the absence of E2 failed to demonstrate lysis of vaccinia-E2-labeled targets. Phenotypically, CTL populations were CD3+/CD8+. These results will facilitate the study of naturally occurring T-cell responses to HPV E2 in patients with cervical intraepithelial neoplasia and the development of immunotherapeutic strategies designed to treat this and other HPV-associated diseases.
    • Human tumor-infiltrating lymphocytes: a marker of host response.

      Vose, Brent M; Moore, Michael; Paterson Laboratories, The Christie Hospital and Holt Radium Institute, Manchester, M20 9BX, UK. (1985-01)
      There is continuing interest in the possibility of immunologic intervention in the therapy of malignant disease. By employing a range of different techniques, it has been possible to show the presence of activated helper, suppressor, and cytotoxic T cells, B cells, NK precursors, and macrophages at the tumor site. The overwhelming impression from our data is that tumors may be subject to immunologic attack by heterogeneous effectors and that there is selective trapping of these effectors with corresponding depletion at the periphery. Like all inflammatory sites, however, the tumor contains both positive and negative regulatory mechanisms with the coexistence of cells with effector and suppressor functions, eg, T suppressors that modulate the proliferative response of T helpers and macrophages suppressing NK function contribute to the dynamic interplay in situ. Additional complexity is indicated by immunohistologic studies that clearly show that the stroma rather than foci of tumor cells are the site of infiltration, thereby further limiting effector function. We are now at the end of the descriptive stage of our investigations and further studies must approach the more difficult problem of modifying the host response in such a way as to alter the balance between effector and suppressor activity. A promising area of research would appear to be the use of cloned helper T cells or their products in the immunotherapy of cancer. The demonstration, by us, of selective trapping at tumor sites suggests that administration of the patients' own T cells with antitumor reactivity may serve as an efficient delivery vehicle to activate host effectors in situ. Studies in animal systems have shown the feasibility of this approach, although the failure of cultured T cells to undergo normal recirculation represents a considerable unresolved problem. Effector function by each of the tumor-infiltrating cell types described is under T cell control, and preliminary studies have already indicated the ability of helper T cells to accelerate allograft and tumor rejection. The increasing availability of gene-cloned materials with potent biologic activity opens new areas of research in cancer therapy. The lymphokines IL-2 and interferon are already undergoing clinical trials. Studies by Hersey demonstrate that administration of conditioned medium containing impure IL-2 results in the appearance of antitumor effectors in previously nonreactive melanoma patients, and Rosenberg, among others, has shown IL-2 to be a potent enhancer of alloimmune responses. Lymphokine-activating macrophages also augment antitumour responses.(ABSTRACT TRUNCATED AT 400 WORDS)
    • Human tumor-lymphocyte interaction in vitro. VI. Specificity of primary and secondary autologous lymphocyte-mediated cytotoxicity.

      Vánky, F; Vose, Brent M; Fopp, M; Klein, E (1979-06)
      A T-cell-enriched lymphocyte subset of samples from 15 tumor patients was tested for primary cytotoxicity against autologous tumor cell preparations and against 1-3 different allogeneic tumor cell preparations from biopsy material. Allogeneic cytotoxicity occurred in only 1 of 10 patients with autologous reactivity. The lymphocytes of 14 patients were cultured with autologous cells from biopsy material for 6 days. These lymphocytes killed autologous targets, but only 1 patient's lymphocytes were cytotoxic against 1 of the 4 allogeneic tumors tested. Cocultivation with allogeneic cells from biopsy specimens generated cytotoxicity toward the sensitizing allogeneic cells in 3 of 9 test combinations. In 2 of 3 instances the effectors were also active against the autologous tumor cells. Cytotoxicity in primary and secondary tests occurred thus only rarely against allogeneic targets. This indicated either the presence of individual tumor-related antigens on the cells from biopsy material or reflected the histocompatibility restriction of T-cell-mediated cytotoxicity.
    • HUWE1 is a critical colonic tumour suppressor gene that prevents MYC signalling, DNA damage accumulation and tumour initiation.

      Myant, K; Cammareri, P; Hodder, M; Wills, J; Von Kriegsheim, A; Győrffy, B; Rashid, M; Polo, S; Maspero, E; Vaughan, Lynsey; et al. (2017-02)
      Cancer genome sequencing projects have identified hundreds of genetic alterations, often at low frequencies, raising questions as to their functional relevance. One exemplar gene is HUWE1, which has been found to be mutated in numerous studies. However, due to the large size of this gene and a lack of functional analysis of identified mutations, their significance to carcinogenesis is unclear. To determine the importance of HUWE1, we chose to examine its function in colorectal cancer, where it is mutated in up to 15 per cent of tumours. Modelling of identified mutations showed that they inactivate the E3 ubiquitin ligase activity of HUWE1. Genetic deletion of Huwe1 rapidly accelerated tumourigenic in mice carrying loss of the intestinal tumour suppressor gene Apc, with a dramatic increase in tumour initiation. Mechanistically, this phenotype was driven by increased MYC and rapid DNA damage accumulation leading to loss of the second copy of Apc The increased levels of DNA damage sensitised Huwe1-deficient tumours to DNA-damaging agents and to deletion of the anti-apoptotic protein MCL1. Taken together, these data identify HUWE1 as a bona fide tumour suppressor gene in the intestinal epithelium and suggest a potential vulnerability of HUWE1-mutated tumours to DNA-damaging agents and inhibitors of anti-apoptotic proteins.
    • Hybridization interactions between probesets in short oligo microarrays lead to spurious correlations.

      Okoniewski, Michal J; Miller, Crispin J; Paterson Institute For Cancer Research, Christie Hospital site, University of Manchester, Wilmslow Road, Manchester, M20 4BX, UK. MOkoniewski@PICR.man.ac.uk (2006)
      BACKGROUND: Microarrays measure the binding of nucleotide sequences to a set of sequence specific probes. This information is combined with annotation specifying the relationship between probes and targets and used to make inferences about transcript- and, ultimately, gene expression. In some situations, a probe is capable of hybridizing to more than one transcript, in others, multiple probes can target a single sequence. These 'multiply targeted' probes can result in non-independence between measured expression levels. RESULTS: An analysis of these relationships for Affymetrix arrays considered both the extent and influence of exact matches between probe and transcript sequences. For the popular HGU133A array, approximately half of the probesets were found to interact in this way. Both real and simulated expression datasets were used to examine how these effects influenced the expression signal. It was found not only to lead to increased signal strength for the affected probesets, but the major effect is to significantly increase their correlation, even in situations when only a single probe from a probeset was involved. By building a network of probe-probeset-transcript relationships, it is possible to identify families of interacting probesets. More than 10% of the families contain members annotated to different genes or even different Unigene clusters. Within a family, a mixture of genuine biological and artefactual correlations can occur. CONCLUSION: Multiple targeting is not only prevalent, but also significant. The ability of probesets to hybridize to more than one gene product can lead to false positives when analysing gene expression. Comprehensive annotation describing multiple targeting is required when interpreting array data.
    • Hydroxychloroquine/ chloroquine as a treatment choice or prophylaxis for Covid-19 at the primary care level in developing countries: A Primum non Nocere dilemma

      Medina MT; Moncada, Salvador; Faculty of Medical Sciences, National Autonomous University of Honduras, WFN Regional Director for Latin America, Tegucigalpa, Honduras. (2020)
      The Food and Drug Administration (FDA) warned against the use of Hydroxychloroquine or chloroquine for Covid-19 outside of a hospital or a clinical trial setting due to the risk of QT interval prolongation, ventricular tachycardia and the increased risk of these complications when combined with some antibiotics such as azithromycin. Several studies have reported no benefit of Hydroxychloroquine or chloroquine, when used alone or with a macrolide in COVID-19 hospitalized patients. Despite these warnings, in several developing countries the official guidelines for treatment of Covid-19 patients at the primary care level recommend Hydroxychloroquine and azithromycin, among other treatments, as the first-choice for mild symptomatic Covid-19 patients, asymptomatic contacts or for prophylaxis. In our opinion there is a primum non nocere dilemma during this Covid-19 pandemic. In order to solve this bioethical problem, we strongly recommend that a randomized controlled trial in a primary care setting be carried out as a matter of urgency in these areas of the world. Keywords: Bioethics; Clinical trials; Developing countries; Hydroxychloroquine/ chloroquine; Primary care.
    • Hypersensitivity to very-low single radiation doses: its relationship to the adaptive response and induced radioresistance.

      Joiner, M C; Lambin, P; Malaise, E P; Robson, T; Arrand, J E; Skov, K A; Marples, Brian; Gray Laboratory, Mount Vernon Hospital, Northwood, Middlesex, UK. joiner@graylab.ac.uk (1996-11-04)
      There is now little doubt of the existence of radioprotective mechanisms, or stress responses, that are upregulated in response to exposure to small doses of ionizing radiation and other DNA-damaging agents. Phenomenologically, there are two ways in which these induced mechanisms operate. First, a small conditioning dose (generally below 30 cGy) may protect against a subsequent, separate, exposure to radiation that may be substantially larger than the initial dose. This has been termed the adaptive response. Second, the response to single doses may itself be dose-dependent so that small acute radiation exposures, or exposures at very low dose rates, are more effective per unit dose than larger exposures above the threshold where the induced radioprotection is triggered. This combination has been termed low-dose hypersensitivity (HRS) and induced radioresistance (IRR) as the dose increases. Both the adaptive response and HRS/IRR have been well documented in studies with yeast, bacteria, protozoa, algae, higher plant cells, insect cells, mammalian and human cells in vitro, and in studies on animal models in vivo. There is indirect evidence that the HRS/IRR phenomenon in response to single doses is a manifestation of the same underlying mechanism that determines the adaptive response in the two-dose case and that it can be triggered by high and low LET radiations as well as a variety of other stress-inducing agents such as hydrogen peroxide and chemotherapeutic agents although exact homology remains to be tested. Little is currently known about the precise nature of this underlying mechanism, but there is evidence that it operates by increasing the amount and rate of DNA repair, rather than by indirect mechanisms such as modulation of cell-cycle progression or apoptosis. Changed expression of some genes, only in response to low and not high doses, may occur within a few hours of irradiation and this would be rapid enough to explain the phenomenon of induced radioresistance although its specific molecular components have yet to be identified.
    • Hypofractionated breast radiotherapy for 1 week versus 3 weeks (FAST-Forward): 5-year efficacy and late normal tissue effects results from a multicentre, non-inferiority, randomised, phase 3 trial

      Murray Brunt, A; Haviland, JS; Wheatley, DA; Sydenham, MA; Alhasso, A; Bloomfield, DJ; Chan, C; Churn, M; Cleator, S; Coles, CE; et al. (2020)
      Background: We aimed to identify a five-fraction schedule of adjuvant radiotherapy (radiation therapy) delivered in 1 week that is non-inferior in terms of local cancer control and is as safe as an international standard 15-fraction regimen after primary surgery for early breast cancer. Here, we present 5-year results of the FAST-Forward trial. Methods: FAST-Forward is a multicentre, phase 3, randomised, non-inferiority trial done at 97 hospitals (47 radiotherapy centres and 50 referring hospitals) in the UK. Patients aged at least 18 years with invasive carcinoma of the breast (pT1-3, pN0-1, M0) after breast conservation surgery or mastectomy were eligible. We randomly allocated patients to either 40 Gy in 15 fractions (over 3 weeks), 27 Gy in five fractions (over 1 week), or 26 Gy in five fractions (over 1 week) to the whole breast or chest wall. Allocation was not masked because of the nature of the intervention. The primary endpoint was ipsilateral breast tumour relapse; assuming a 2% 5-year incidence for 40 Gy, non-inferiority was predefined as ?1·6% excess for five-fraction schedules (critical hazard ratio [HR] of 1·81). Normal tissue effects were assessed by clinicians, patients, and from photographs. This trial is registered at isrctn.com, ISRCTN19906132. Findings: Between Nov 24, 2011, and June 19, 2014, we recruited and obtained consent from 4096 patients from 97 UK centres, of whom 1361 were assigned to the 40 Gy schedule, 1367 to the 27 Gy schedule, and 1368 to the 26 Gy schedule. At a median follow-up of 71·5 months (IQR 71·3 to 71·7), the primary endpoint event occurred in 79 patients (31 in the 40 Gy group, 27 in the 27 Gy group, and 21 in the 26 Gy group); HRs versus 40 Gy in 15 fractions were 0·86 (95% CI 0·51 to 1·44) for 27 Gy in five fractions and 0·67 (0·38 to 1·16) for 26 Gy in five fractions. 5-year incidence of ipsilateral breast tumour relapse after 40 Gy was 2·1% (1·4 to 3·1); estimated absolute differences versus 40 Gy in 15 fractions were -0·3% (-1·0 to 0·9) for 27 Gy in five fractions (probability of incorrectly accepting an inferior five-fraction schedule: p=0·0022 vs 40 Gy in 15 fractions) and -0·7% (-1·3 to 0·3) for 26 Gy in five fractions (p=0·00019 vs 40 Gy in 15 fractions). At 5 years, any moderate or marked clinician-assessed normal tissue effects in the breast or chest wall was reported for 98 of 986 (9·9%) 40 Gy patients, 155 (15·4%) of 1005 27 Gy patients, and 121 of 1020 (11·9%) 26 Gy patients. Across all clinician assessments from 1-5 years, odds ratios versus 40 Gy in 15 fractions were 1·55 (95% CI 1·32 to 1·83, p<0·0001) for 27 Gy in five fractions and 1·12 (0·94 to 1·34, p=0·20) for 26 Gy in five fractions. Patient and photographic assessments showed higher normal tissue effect risk for 27 Gy versus 40 Gy but not for 26 Gy versus 40 Gy. Interpretation: 26 Gy in five fractions over 1 week is non-inferior to the standard of 40 Gy in 15 fractions over 3 weeks for local tumour control, and is as safe in terms of normal tissue effects up to 5 years for patients prescribed adjuvant local radiotherapy after primary surgery for early-stage breast cancer.
    • Hypoxia and angiogenic biomarkers in prostate cancer after external beam radiotherapy (EBRT) alone or combined with high-dose-rate brachytherapy boost (HDR-BTb)

      Bhattacharya, IS; Taghavi, Azar SM; Alonzi, R; Hoskin, Peter J; Institute of Cancer Research Clinical Trials and Statistics Unit (ICR-CTSU), London, United Kingdom (2019)
      PURPOSE: To investigate angiogenic and hypoxia biomarkers to predict outcome in patients receiving external beam radiotherapy (EBRT) alone or combined with high-dose-rate brachytherapy boost (HDR-BTb) for localised prostate cancer. METHODS: Prostate biopsy samples were collected prospectively in patients entered into a phase 3 randomised controlled trial of patients receiving EBRT or EBRT?+?HDR-BTb. Univariate and multivariate analyses using Cox proportional hazards model were performed to identify associations between immunohistochemical staining of hypoxia inducible factor 1 alpha (HIF1?), glucose transporter 1 (GLUT1), osteopontin (OPN) and microvessel density (MVD) using CD-34 antibody with clinical outcome. The primary endpoint was biochemical relapse free survival (BRFS) and secondary endpoint was distant metastasis free survival (DMFS). RESULTS: Immunohistochemistry was available for 204 patients. Increased OPN (Hazard ratio [HR] 2.38, 95% Confidence Interval [CI] 1.06-5.34, p?<?0.036) and GLUT1 (HR 2.36, 95%CI 1.39-4.01, p?<?0.001) expression were predictive of worse BRFS. Increased GLUT1 expression (HR 2.22, 1.02-4.84, p?=?0.045) was predictive of worse DMFS. Increased MVD (CD-34) (HR 1.82, 95%CI 1.06-3.14, p?=?0.03) and OPN (HR 1.82, 95%CI 1.06-3.14, p?=?0.03) but reduced GLUT1 expression (HR 0.40, 95%CI 0.20-0.79, p?=?0.009) were predictive of improved BRFS in patients receiving EBRT?+?HDR-BTb. CONCLUSION: Our data suggest angiogenic and hypoxia biomarkers may predict outcome and benefit of dose escalation, however further validation in prospective studies including hypoxia modification is needed. Trial registration number ISRCTN98241100, registered with ISRCTN at http://www.controlled-trials.com/isrctn/.