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1.
JCO Glob Oncol ; 10: e2300403, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38870437

RESUMO

PURPOSE: Prostate cancer disproportionately affects men of African descent, yet their representation in tissue-based studies is limited. This multinational, multicenter pilot study aims to establish the groundwork for collaborative research on prostate cancer in sub-Saharan Africa. METHODS: The Men of African Descent and Carcinoma of the Prostate network formed a pathologist working group representing eight institutions in five African countries. Formalin-fixed paraffin-embedded prostate tissue specimens were collected from Senegal, Nigeria, and Ghana. Histology slides were produced and digitally scanned. A central genitourinary pathologist (P.L.) and eight African general pathologists reviewed anonymized digital whole-slide images for International Society of Urological Pathology grade groups and other pathologic parameters. Discrepancies were re-evaluated, and consensus grading was assigned. A virtual training seminar on prostate cancer grading was followed by a second assessment on a subcohort of the same tissue set. RESULTS: Of 134 tissue blocks, 133 had evaluable tissue; 13 lacked cancer evidence, and four were of insufficient quality. Post-training, interobserver agreement for grade groups improved to 56%, with a median Cohen's quadratic weighted kappa of 0.83 (mean, 0.74), compared with an initial 46% agreement and a quadratic weighted kappa of 0.77. Interobserver agreement between African pathologist groups was 40%, with a quadratic weighted kappa of 0.66 (95% CI, 0.51 to 0.76). African pathologists tended to overgrade (36%) more frequently than undergrade (18%) compared with the reference genitourinary pathologist. Interobserver variability tended to worsen with a decrease in tissue quality. CONCLUSION: Tissue-based studies on prostate cancer in men of African descent are essential for a better understanding of this common disease. Standardized tissue handling protocols are crucial to ensure good tissue quality and data. The use of digital slide imaging can enhance collaboration among pathologists in multinational, multicenter studies.


Assuntos
Neoplasias da Próstata , Masculino , Humanos , Neoplasias da Próstata/patologia , África Subsaariana , Projetos Piloto , Gradação de Tumores
2.
Int J Cancer ; 155(2): 251-260, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38577820

RESUMO

Human papillomavirus (HPV) proteins may elicit antibody responses in the process toward HPV-related malignancy. However, HPV seroepidemiology in noncervical HPV-related cancers remains poorly understood, particularly in populations with a high prevalence of human immunodeficiency virus (HIV). Using a glutathione S-transferase-based multiplex serology assay, antibodies against E6, E7 and L1 proteins of HPV16 and HPV18 were measured in sera of 535 cases of noncervical HPV-related cancers (anal (n = 104), vulval (n = 211), vaginal (n = 49), penile (n = 37) and oropharyngeal (n = 134)) and 6651 non-infection-related cancer controls, from the Johannesburg Cancer Study that recruited Black South African with newly diagnosed cancer between 1995 and 2016. Logistic and Poisson regression models were used to calculate adjusted odds ratios (aOR) and prevalence ratios (aPR) and 95% confidence intervals (CI) in cases versus controls. HPV16 E6 was more strongly associated with noncervical HPV-related cancers than HPV16 L1 or E7, or HPV18 proteins: anal (females (HPV16 E6 aOR = 11.50;95%CI:6.0-22.2), males (aOR = 10.12;95%CI:4.9-20.8), vulval (aOR = 11.69;95%CI:7.9-17.2), vaginal (aOR = 10.26;95%CI:5.0-21), penile (aOR = 18.95;95%CI:8.9-40), and oropharyngeal (females (aOR = 8.95;95%CI:2.9-27.5), males (aOR = 3.49;95%CI:1.8-7.0)) cancers. HPV16-E6 seropositivity ranged from 24.0% to 35.1% in anal, vulval, vaginal and penile cancer but was significantly lower (11.2%) in oropharyngeal cancer. After adjustment for HIV, prevalence of which increased from 22.2% in 1995-2005 to 54.1% in 2010-2016, HPV16 E6 seropositivity increased by period of diagnosis (aPR for 2010-2016 vs. 1995-2006 = 1.84;95%CI:1.1-3.0). Assuming HPV16 E6 seroprevalence reflects HPV attributable fraction, the proportion of certain noncervical-HPV-related cancers caused by HPV is increasing over time in South Africa. This is expected to be driven by the increasing influence of HIV.


Assuntos
Anticorpos Antivirais , Infecções por HIV , Proteínas Oncogênicas Virais , Infecções por Papillomavirus , Humanos , Masculino , Feminino , África do Sul/epidemiologia , Infecções por Papillomavirus/virologia , Infecções por Papillomavirus/epidemiologia , Infecções por Papillomavirus/imunologia , Pessoa de Meia-Idade , Adulto , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Proteínas Oncogênicas Virais/imunologia , Infecções por HIV/epidemiologia , Infecções por HIV/virologia , Papillomavirus Humano 16/imunologia , Idoso , Neoplasias Orofaríngeas/virologia , Neoplasias Orofaríngeas/epidemiologia , Estudos Soroepidemiológicos , Estudos de Casos e Controles , Papillomavirus Humano 18/imunologia , Neoplasias Vulvares/virologia , Neoplasias Vulvares/epidemiologia , Neoplasias Vulvares/sangue , Neoplasias Penianas/virologia , Neoplasias Penianas/epidemiologia , Neoplasias Penianas/sangue , Neoplasias do Ânus/virologia , Neoplasias do Ânus/epidemiologia , Neoplasias do Ânus/sangue , Neoplasias Vaginais/virologia , Neoplasias Vaginais/epidemiologia , População Negra , Proteínas Repressoras/imunologia , Neoplasias/epidemiologia , Neoplasias/virologia , Neoplasias/sangue , Neoplasias/imunologia , Papillomavirus Humano
3.
Clin Epigenetics ; 16(1): 56, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38643219

RESUMO

BACKGROUND: Cervical cancer remains a leading cause of death, particularly in developing countries. WHO screening guidelines recommend human papilloma virus (HPV) detection as a means to identify women at risk of developing cervical cancer. While HPV testing identifies those at risk, it does not specifically distinguish individuals with neoplasia. We investigated whether a quantitative molecular test that measures methylated DNA markers could identify high-risk lesions in the cervix with accuracy. RESULTS: Marker discovery was performed in TCGA-CESC Infinium Methylation 450 K Array database and verified in three other public datasets. The panel was technically validated using Quantitative Multiplex-Methylation-Specific PCR in tissue sections (N = 252) and cervical smears (N = 244) from the USA, South Africa, and Vietnam. The gene panel consisted of FMN2, EDNRB, ZNF671, TBXT, and MOS. Cervical tissue samples from all three countries showed highly significant differential methylation in squamous cell carcinoma (SCC) with a sensitivity of 100% [95% CI 74.12-100.00], and specificity of 91% [95% CI 62.26-99.53] to 96% [95% CI 79.01-99.78], and receiver operating characteristic area under the curve (ROC AUC) = 1.000 [95% CI 1.00-1.00] compared to benign cervical tissue, and cervical intraepithelial neoplasia 2/3 with sensitivity of 55% [95% CI 37.77-70.84] to 89% [95% CI 67.20-98.03], specificity of 93% [95% CI 84.07-97.38] to 96% [95% CI 79.01-99.78], and a ROC AUC ranging from 0.793 [95% CI 0.68-0.89] to 0.99 [95% CI 0.97-1.00] compared to CIN1. In cervical smears, the marker panel detected SCC with a sensitivity of 87% [95% CI 77.45-92.69], specificity 95% [95% CI 88.64-98.18], and ROC AUC = 0.925 [95% CI 0.878-0.974] compared to normal, and high-grade squamous intraepithelial lesion (HSIL) at a sensitivity of 70% (95% CI 58.11-80.44), specificity of 94% (95% CI 88.30-97.40), and ROC AUC = 0.884 (95% CI 0.822-0.945) compared to low-grade intraepithelial lesion (LSIL)/normal in an analysis of pooled data from the three countries. Similar to HPV-positive, HPV-negative cervical carcinomas were frequently hypermethylated for these markers. CONCLUSIONS: This 5-marker panel detected SCC and HSIL in cervical smears with a high level of sensitivity and specificity. Molecular tests with the ability to rapidly detect high-risk HSIL will lead to timely treatment for those in need and prevent unnecessary procedures in women with low-risk lesions throughout the world. Validation of these markers in prospectively collected cervical smear cells followed by the development of a hypermethylated marker-based cervical cancer detection test is warranted.


Assuntos
Carcinoma de Células Escamosas , Infecções por Papillomavirus , Neoplasias do Colo do Útero , Humanos , Feminino , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/patologia , Países em Desenvolvimento , Infecções por Papillomavirus/diagnóstico , Infecções por Papillomavirus/genética , Marcadores Genéticos , Metilação de DNA , Carcinoma de Células Escamosas/genética , Papillomaviridae/genética , Esfregaço Vaginal/métodos , Proteínas Supressoras de Tumor/genética
4.
PLoS One ; 19(4): e0298668, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38625919

RESUMO

Limax maximus, or great gray slug, is a common agriculture pest. The pest infests crops during their growth phase, creating holes in vegetable leaves, particularly in seedlings and tender leaves. A study was conducted to assess the insecticidal activity of Ageratina adenophora extract against these slugs. Factors such as fecundity, growth, hatching rate, offspring survival rate, protective enzyme activity, and detoxifying enzyme activity were examined in slugs exposed to the extract's sublethal concentration (LC50) for two different durations (24 and 48 h). The phytochemical variability of the extracts was also studied. The LC50 value of the A. adenophora extract against L. maximus was 35.9 mg/mL. This extract significantly reduced the hatching rate of eggs and the survival rate of offspring hatched from exposed eggs compared with the control. The lowest rates were observed in those exposed for 48 h. The survival, growth, protective enzyme, and detoxification activity of newly hatched and 40-day-old slugs decreased. The A. adenophora extract contained tannins, flavonoids, and saponins, possibly contributing to their biological effects. These results suggest that the extract could be used as an alternative treatment for slug extermination, effectively controlling this species.


Assuntos
Ageratina , Asteraceae , Gastrópodes , Inseticidas , Animais , Inseticidas/farmacologia , Moluscos , Extratos Vegetais/farmacologia
5.
Front Immunol ; 15: 1331841, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38370403

RESUMO

Background: Breast cancer (BRCA) is a common malignancy in women, and its resistance to immunotherapy is a major challenge. Abnormal expression of genes is important in the occurrence and development of BRCA and may also affect the prognosis of patients. Although many BRCA prognosis model scores have been developed, they are only applicable to a limited number of disease subtypes. Our goal is to develop a new prognostic score that is more accurate and applicable to a wider range of BRCA patients. Methods: BRCA patient data from The Cancer Genome Atlas database was used to identify breast cancer-related genes (BRGs). Differential expression analysis of BRGs was performed using the 'limma' package in R. Prognostic BRGs were identified using co-expression and univariate Cox analysis. A predictive model of four BRGs was established using Cox regression and the LASSO algorithm. Model performance was evaluated using K-M survival and receiver operating characteristic curve analysis. The predictive ability of the signature in immune microenvironment and immunotherapy was investigated. In vitro experiments validated POLQ function. Results: Our study identified a four-BRG prognostic signature that outperformed conventional clinicopathological characteristics in predicting survival outcomes in BRCA patients. The signature effectively stratified BRCA patients into high- and low-risk groups and showed potential in predicting the response to immunotherapy. Notably, significant differences were observed in immune cell abundance between the two groups. In vitro experiments demonstrated that POLQ knockdown significantly reduced the viability, proliferation, and invasion capacity of MDA-MB-231 or HCC1806 cells. Conclusion: Our 4-BRG signature has the potential as an independent biomarker for predicting prognosis and treatment response in BRCA patients, complementing existing clinicopathological characteristics.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/genética , Neoplasias da Mama/terapia , Prognóstico , Mama , Biologia Computacional , Imunoterapia , Microambiente Tumoral/genética
6.
J Econ Entomol ; 117(1): 302-310, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38011902

RESUMO

Toxoptera aurantii is one of the most destructive pests, threatening the yield and quality of tea plantations. The salicylic acid (SA)-mediated signaling pathway is vital for the induction of plant defense responses; however, its role in tea plant resistance to T. aurantii remains unclear. Thus, this study used and electrical penetration graph and monitoring of population dynamics to evaluate the effects of exogenous SA application on T. aurantii feeding behavior and population growth in tea seedlings. Moreover, the effects of SA treatment on the activities of defense-related enzymes were analyzed. Probe counts and the duration of xylem sap ingestion were significantly higher in SA-treated plants than those in the control group. The total duration of passive phloem ingestion was significantly decreased in 0.5 mmol/l SA-treated plants, and the application of 0.5, 1, and 4 mmol/l SA significantly inhibited T. aurantii population growth. In addition, the activities of polyphenol oxidase, peroxidase, and superoxide dismutase were significantly increased in the 0.5 mmol/l SA-treated plants. Overall, this study demonstrates the capacity of exogenous SA to activate defense responses against T. aurantii. These results have crucial implications for understanding the mechanisms of enhanced resistance, thereby providing a sustainable approach for managing T. aurantii.


Assuntos
Afídeos , Animais , Afídeos/fisiologia , Ácido Salicílico/farmacologia , Ácido Salicílico/metabolismo , Chá
7.
Cancer Med ; 2023 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-38158645

RESUMO

BACKGROUND: Men of African descent are disproportionately affected by prostate cancer (PCa), and many have metastatic disease at presentation. In South Africa (SA), androgen deprivation therapy (ADT) is the first-line treatment for stage IV PCa. OBJECTIVE: To identify predictors of overall survival (OS) in Black South African men with stage IV PCa treated with ADT. DESIGN, SETTING, AND PARTICIPANTS: Men diagnosed with prostate cancer (3/22/2016-10/30/2020) at Chris Hani Baragwanath Academic Hospital in Soweto, Johannesburg, were recruited for the Men of African Descent with Cancer of the Prostate study. We included men with newly diagnosed stage IV PCa treated with ADT who had a prostate-specific antigen (PSA) level drawn prior to initiation of ADT and had ≥1 PSA drawn ≥12 weeks after ADT start. OUTCOMES MEASURES AND STATISTICAL ANALYSIS: We used Kaplan-Meier statistics to estimate OS and Cox regression models to identify predictors of OS. RESULTS AND LIMITATIONS: Of the 1097 men diagnosed with prostate cancer, we included 153 men with stage IV PCa who received ADT and met PSA requirements. The median age was 68.0 years (interquartile range 64-73 years). Median OS from time of ADT initiation was 3.39 years (95% confidence interval (CI): 3.14%-noncalculable), while biochemical progression-free survival was 2.36 years (95% CI: 2.03%-3.73%). Biochemical progression (HR 3.52, 95% CI: 1.85%-6.70%), PSA nadir level >4 ng/mL (HR 3.77, 95% CI: 1.86%-7.62%), alkaline phosphatase level at diagnosis >150 IU/dL (HR 3.09, 95% CI: 1.64%-5.83%), and hemoglobin at diagnosis <13.5 g/dL (HR 2.90, 95% CI: 1.28%-6.56%) were associated with worse OS. CONCLUSIONS: In this study, we identified factors associated with poor OS among Black South African men with stage IV PCa treated with ADT. These factors may be useful in identifying patients for upfront treatment escalation, including the use of docetaxel chemotherapy or escalation of therapy at the time of biochemical progression. PATIENT SUMMARY: In this study, we found that high alkaline phosphatase level, anemia at diagnosis, and high PSA nadir after initiation of androgen deprivation therapy are associated with worse overall survival among Black South African men treated with androgen deprivation therapy for metastatic prostate cancer.

8.
medRxiv ; 2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37961155

RESUMO

We conducted a multi-ancestry genome-wide association study of prostate-specific antigen (PSA) levels in 296,754 men (211,342 European ancestry; 58,236 African ancestry; 23,546 Hispanic/Latino; 3,630 Asian ancestry; 96.5% of participants were from the Million Veteran Program). We identified 318 independent genome-wide significant (p≤5e-8) variants, 184 of which were novel. Most demonstrated evidence of replication in an independent cohort (n=95,768). Meta-analyzing discovery and replication (n=392,522) identified 447 variants, of which a further 111 were novel. Out-of-sample variance in PSA explained by our new polygenic risk score reached 16.9% (95% CI=16.1%-17.8%) in European ancestry, 9.5% (95% CI=7.0%-12.2%) in African ancestry, 18.6% (95% CI=15.8%-21.4%) in Hispanic/Latino, and 15.3% (95% CI=12.7%-18.1%) in Asian ancestry, and lower for higher age. Our study highlights how including proportionally more participants from underrepresented populations improves genetic prediction of PSA levels, with potential to personalize prostate cancer screening.

9.
PLOS Glob Public Health ; 3(10): e0002432, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37874786

RESUMO

The South African Breast Cancer and HIV Outcomes prospective cohort (SABCHO) study was established to investigate survival determinants among HIV-positive and HIV-negative SA women with breast cancer. This paper describes common and unique characteristics of the cancer centres and their participants, examining disparities in pathways to diagnosis, treatment resources and approaches adopted to mitigate resource constraints. The Johannesburg (Jhb), Soweto (Sow), and Durban (Dbn) sites treat mainly urban, relatively better educated and more socioeconomically advantaged patients whereas the Pietermaritzburg (Pmb) and Empangeni (Emp) sites treat predominantly rural, less educated and more impoverished communities The Sow, Jhb, and Emp sites had relatively younger patients (mean ages 54 ±14.5, 55±13.7 and 54±14.3 respectively), whereas patients at the Dbn and Pmb sites, with greater representation of Asian Indian women, were relatively older (mean age 57 ±13.9 and 58 ±14.6 respectively). HIV prevalence among the cohort was high, ranging from 15%-42%, (Cohort obesity (BMI ≥ 30 kg/m2) at 60%, self-reported hypertension (41%) and diabetes (13%). Direct referral of patients from primary care clinics to cancer centre occurred only at the Sow site which uniquely ran an open clinic and where early stage (I and II) proportions were highest at 48.5%. The other sites relied on indirect patient referral from regional hospitals where significant delays in diagnostics occurred and early-stage proportions were a low (15%- 37.3%). The Emp site referred patients for all treatments to the Dbn site located 200km away; the Sow site provided surgery and endocrine treatment services but referred patients to the Jhb site 30 Km away for chemo- and radiation therapy. The Jhb, Dbn and Pmb sites all provided complete oncology treatment services. All treatment centres followed international guidelines for their treatment approaches. Findings may inform policy interventions to address national and regional disparities in breast cancer care.

10.
Res Sq ; 2023 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-37886553

RESUMO

Men of African descent have the highest prostate cancer (CaP) incidence and mortality rates, yet the genetic basis of CaP in African men has been understudied. We used genomic data from 3,963 CaP cases and 3,509 controls recruited in Ghana, Nigeria, Senegal, South Africa, and Uganda, to infer ancestry-specific genetic architectures and fine-mapped disease associations. Fifteen independent associations at 8q24.21, 6q22.1, and 11q13.3 reached genome-wide significance, including four novel associations. Intriguingly, multiple lead SNPs are private alleles, a pattern arising from recent mutations and the out-of-Africa bottleneck. These African-specific alleles contribute to haplotypes with odds ratios above 2.4. We found that the genetic architecture of CaP differs across Africa, with effect size differences contributing more to this heterogeneity than allele frequency differences. Population genetic analyses reveal that African CaP associations are largely governed by neutral evolution. Collectively, our findings emphasize the utility of conducting genetic studies that use diverse populations.

11.
Am J Hum Genet ; 110(10): 1690-1703, 2023 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-37673066

RESUMO

Esophageal squamous cell carcinoma (ESCC) has a high disease burden in sub-Saharan Africa and has a very poor prognosis. Genome-wide association studies (GWASs) of ESCC in predominantly East Asian populations indicate a substantial genetic contribution to its etiology, but no genome-wide studies have been done in populations of African ancestry. Here, we report a GWAS in 1,686 African individuals with ESCC and 3,217 population-matched control individuals to investigate its genetic etiology. We identified a genome-wide-significant risk locus on chromosome 9 upstream of FAM120A (rs12379660, p = 4.58 × 10-8, odds ratio = 1.28, 95% confidence interval = 1.22-1.34), as well as a potential African-specific risk locus on chromosome 2 (rs142741123, p = 5.49 × 10-8) within MYO1B. FAM120A is a component of oxidative stress-induced survival signals, and the associated variants at the FAM120A locus co-localized with highly significant cis-eQTLs in FAM120AOS in both esophageal mucosa and esophageal muscularis tissue. A trans-ethnic meta-analysis was then performed with the African ESCC study and a Chinese ESCC study in a combined total of 3,699 ESCC-affected individuals and 5,918 control individuals, which identified three genome-wide-significant loci on chromosome 9 at FAM120A (rs12379660, pmeta = 9.36 × 10-10), chromosome 10 at PLCE1 (rs7099485, pmeta = 1.48 × 10-8), and chromosome 22 at CHEK2 (rs1033667, pmeta = 1.47 × 10-9). This indicates the existence of both shared and distinct genetic risk loci for ESCC in African and Asian populations. Our GWAS of ESCC conducted in a population of African ancestry indicates a substantial genetic contribution to ESCC risk in Africa.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Humanos , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Estudos de Casos e Controles , População do Leste Asiático , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/epidemiologia , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/genética , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Polimorfismo de Nucleotídeo Único/genética , População Africana
12.
Front Oncol ; 13: 1109181, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37621680

RESUMO

Background: Extracellular matrix (ECM) remodeling is one of the hallmark events in cancer and has been shown to be closely related to tumor immunity. Immunotherapy has evolved as an important tool to treat various cancers and improve patient prognosis. The positive response to immunotherapy relies on the unique interaction between cancer and the tumor microenvironment (TME). However, the relationship between ECM remodeling and clinical outcomes, immune cell infiltration, and immunotherapy in colorectal cancer (CRC) remains unknown. Methods: We systematically evaluated 69 ECM remodeling-associated genes (EAGs) and comprehensively identified interactions between ECM remodeling and prognosis and the immune microenvironment in CRC patients. The EAG_score was used to quantify the subtype of ECM remodeling in patients. We then assessed their value in predicting prognosis and responding to treatment in CRC. Results: After elaborating the molecular characteristics of ECM remodeling-related genes in CRC patients, a model consisting of two ECM remodeling-related genes (MEIS2, SLC2A3) was developed for predicting the prognosis of CRC patients, Receiver Operating Characteristic (ROC) and Kaplan-Meier (K-M) analysis verified its reliable predictive ability. Furthermore, we created a highly reliable nomogram to enhance the clinical feasibility of the EAG_score. Significantly differences in TME and immune function, such as macrophages and CD8+ T cells, were observed between high- and low-risk CRC patients. In addition, drug sensitivity is also strongly related to EAG_score. Conclusion: Overall, we developed a prognostic model associated with ECM remodeling, provided meaningful clinical implications for immunotherapy, and facilitated individualized treatment for CRC patients. Further studies are needed to reveal the underlying mechanisms of ECM remodeling in CRC.

13.
Adv Healthc Mater ; 12(25): e2300503, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37306493

RESUMO

Photodynamic therapy (PDT) uses photosensitizers to convert oxygen (O2 ) to reactive oxygen species (ROS) under irradiation to induce DNA damage and kill cancer cells. However, the effect of PDT is usually alleviated by apoptosis resistance mechanism of tumor living cells. MTH1 enzyme is known to be such an apoptosis-resistance enzyme which is over expressed as a scavenger to repair the damaged DNA. In this work, a hypoxia-activated nanosystem FTPA, which can be degraded to release the encapsulated PDT photosensitizer 4-DCF-MPYM and an inhibitor TH588 is proposed. The inhibitor TH588 can inhibit the DNA repair process by reducing the activity of MTH1 enzyme, and achieve the purpose of amplifying the therapeutic effect of PDT. This work demonstrates that a precise and augmented tumor PDT is achieved by integration of hypoxia-activation and inhibition resistance of tumor cells to apoptosis.


Assuntos
Fotoquimioterapia , Humanos , Linhagem Celular Tumoral , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Espécies Reativas de Oxigênio/metabolismo , Oxigênio , Hipóxia/tratamento farmacológico , Apoptose
14.
J Gastrointest Oncol ; 14(2): 705-718, 2023 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-37201060

RESUMO

Background: Colorectal cancer (CRC) is the third most common cancer worldwide and one of the leading causes of cancer-related death. Peptidomics, considered a novel branch of proteomics, has an increasing range of applications in the screening, diagnosis, prognosis, and even monitoring of cancer. However, there is little information for peptidomics analysis in CRC. Methods: In this study, a comparative peptidomic profiling was analyzed in 3 CRC tissue samples and 3 adjacent intestinal epithelial tissue samples by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Results: Among the total 133 nonredundant peptides identified, 59 were significantly differentially expressed in the CRC samples and benign colonic epithelium conditions [fold change (FC) >2, P<0.05]. Totals of 25 up-regulated and 34 down-regulated peptides were detected, respectively. Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis were applied to predict the possible functions of these relevant precursor proteins. To clearly identify the potential interaction network of peptide precursors, the Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) was used to determine protein interactions and a possible central role in CRC. Conclusions: Our results for the first time revealed the differentially expressed peptides between the serous CRC tissue and the adjacent intestinal epithelial tissue samples, and these prominently variable peptides might have an important potential role in occurrence and development of CRC.

15.
Chembiochem ; 24(16): e202300323, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37169724

RESUMO

Photodynamic therapy (PDT) is one common ROS-generating therapeutic method with high tumor selectivity and low side effects. But the GSH-upregulation often alleviates its therapeutic efficiency. Here, we proposed a new strategy of jointly depleting GSH to enhance the therapeutic effect of PDT by preparing a nanomicelle by self-assembly method from GSH-activated photosensitizer DMT, curcumin, and amphiphilic polymer TPGS.


Assuntos
Curcumina , Nanopartículas , Neoplasias , Fotoquimioterapia , Humanos , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Neoplasias/tratamento farmacológico , Curcumina/farmacologia , Glutationa , Linhagem Celular Tumoral
16.
Clin Pharmacol Ther ; 114(1): 127-136, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37042388

RESUMO

Clinical outcomes of tamoxifen (TAM) treatment show wide interindividual variability. Comedications and genetic polymorphisms of enzymes involved in TAM metabolism contributes to this variability. Drug-drug and drug-gene interactions have seldom been studied in African Black populations. We evaluated the effects of commonly co-administered medicines on TAM pharmacokinetics in a cohort of 229 South African Black female patients with hormone-receptor positive breast cancer. We also investigated the pharmacokinetic effects of genetic polymorphism in enzymes involved in TAM metabolism, including the variants CYP2D6*17 and *29, which have been mainly reported in people of African descent. TAM and its major metabolites, N-desmethyltamoxifen (NDM), 4-OH-tamoxifen, and endoxifen (ENDO), were quantified in plasma using the liquid chromatography-mass spectrometry. The GenoPharm open array was used to genotype CYP2D6, CYP3A5, CYP3A4, CYP2B6, CYP2C9, and CYP2C19. Results showed that CYP2D6 diplotype and CYP2D6 phenotype significantly affected endoxifen concentration (P < 0.001 and P < 0.001). CYP2D6*17 and CYP2D6*29 significantly reduced the metabolism of NDM to ENDO. Antiretroviral therapy had a significant effect on NDM levels and the TAM/NDM and NDM/ENDO metabolic ratios but did not result in significant effects on ENDO levels. In conclusion, CYP2D6 polymorphisms affected endoxifen concentration and the variants CYP2D6*17 and CYP2D6*29 significantly contributed to low exposure levels of ENDO. This study also suggests a low risk of drug-drug interaction in patients with breast cancer on TAM.


Assuntos
Citocromo P-450 CYP2D6 , Neoplasias , Feminino , Humanos , Citocromo P-450 CYP2D6/genética , Citocromo P-450 CYP2D6/metabolismo , África do Sul , Tamoxifeno , Genótipo , Polimorfismo Genético/genética , Neoplasias/tratamento farmacológico , Antineoplásicos Hormonais/uso terapêutico
17.
Oncologist ; 28(10): e921-e929, 2023 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-36943395

RESUMO

INTRODUCTION: In the South African Breast Cancer and HIV Outcomes (SABCHO) study, we previously found that breast cancer patients living with HIV and treated with neoadjuvant chemotherapy achieve lower rates of complete pathologic response than patients without HIV. We now assess the impact of comorbid HIV on receipt of timely and complete neoadjuvant and adjuvant chemotherapy. MATERIALS AND METHODS: Since June 2015, the SABCHO study has collected data on women diagnosed with breast cancer at 6 South African hospitals. We selected a sample of participants with stages I-III cancer who received ≥2 doses of neoadjuvant or adjuvant chemotherapy. Data on chemotherapies prescribed and received, filgrastim receipt, and laboratory values measured during treatment were captured from patients' medical records. We calculated the mean relative dose intensity (RDI) for all prescribed chemotherapies. We tested for association between full regimen RDI and HIV status, using linear regression to control for demographic and clinical covariates, and for association of HIV with laboratory abnormalities. RESULTS: The 166 participants living with HIV and 159 without HIV did not differ in median chemotherapy RDI: 0.89 (interquartile range (IQR) 0.77-0.95) among those living with HIV and 0.87 (IQR 0.77-0.94) among women without HIV. Patients living with HIV experienced more grade 3+ anemia and leukopenia than those without HIV (anemia: 10.8% vs. 1.9%, P = .001; leukopenia: 8.4% vs. 1.9%, P = .008) and were more likely to receive filgrastim (24.7% vs. 10.7%, P = .001). CONCLUSIONS: HIV status did not impact neoadjuvant or adjuvant chemotherapy RDI, although patients with breast cancer living with HIV experienced more myelotoxicity during treatment.


Assuntos
Neoplasias da Mama , Infecções por HIV , Leucopenia , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Terapia Neoadjuvante/efeitos adversos , Filgrastim/uso terapêutico , Infecções por HIV/tratamento farmacológico , África do Sul/epidemiologia , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Quimioterapia Adjuvante/efeitos adversos
18.
J Am Chem Soc ; 145(14): 8130-8140, 2023 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-37001012

RESUMO

Type I photosensitization provides an effective solution to the problem of unsatisfactory photodynamic therapeutic (PDT) effects caused by the tumor hypoxia. The challenge in the development of Type I mode is to boost the photosensitizer's own electron transfer capacity. Herein, we found that the use of bovine serum albumin (BSA) to encapsulate a thermally activated delayed fluorescence (TADF) photosensitizer PS can significantly promote the Type I PDT process to generate a mass of superoxide anions (O2•-). This Type I photosensitization opened a new strategy by employing BSA as "electron reservoir" and TADF photosensitizer as "electron pump". We integrated these roles of BSA and PS in one system by preparing nanophotosensitizer PS@BSA. The Type I PDT performance was demonstrated with tumor cells under hypoxic conditions. Furthermore, PS@BSA took full advantage of the tumor-targeting role of BSA and achieved efficient PDT for tumor-bearing mice in the in vivo experiments. This work provides an effective route to improve the PDT efficiency of hypoxic tumors.


Assuntos
Neoplasias , Fotoquimioterapia , Animais , Camundongos , Fármacos Fotossensibilizantes/uso terapêutico , Soroalbumina Bovina , Fluorescência , Elétrons , Neoplasias/tratamento farmacológico , Hipóxia/tratamento farmacológico
19.
Int J Cancer ; 152(10): 2081-2089, 2023 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-36727526

RESUMO

Kaposi sarcoma-associated herpesvirus (KSHV) causes Kaposi sarcoma (KS). The risk of KS is amplified in HIV-immunosuppressed individuals and antiretroviral therapy (ART) reduces KS incidence. Reliable data on the relationship between these factors are lacking in Africa. We used questionnaires and serum from 7886 black South Africans (18-74 years) with incident cancer, recruited between 1995 and 2016. ART rollout started in 2004. We measured associations between KS, HIV-1 and KSHV before and after ART rollout. We measured seropositivity to HIV-1, KSHV latency-associated nuclear antigen (LANA) and glycoprotein (K8.1) and calculated case-control-adjusted odds ratios (ORadj ) and 95% confidence intervals (CI) in relation to KS and KSHV infection, before (1995-2004), early (2005-2009) and late (2010-2016) ART rollout periods. KSHV seropositivity among 1237 KS cases was 98%. Among 6649 controls, KSHV seropositivity was higher in males (ORadj  = 1.4 [95%CI 1.23-1.52]), in persons with HIV, (ORadj  = 4.2 [95%CI 3.74-4.73]) and lower in high school leavers (ORadj  = 0.7 [95%CI 0.59-0.83]). KSHV seropositivity declined over the three ART rollout periods (37%, 28% and 28%, Ptrend < .001) coinciding with increases in high school leavers over the same periods (46%, 58% and 67%, Ptrend < .001). HIV-1 seroprevalence increased from 10% in the pre-ART period to 22% in the late ART period (Ptrend < .001). Compared to HIV-1 and KSHV seronegatives, KSHV seropositives yielded an OR for KS of 26 (95%CI 11-62) in HIV-1 seronegative participants and an OR of 2501 (95%CI 1083-5776) in HIV-1 seropositive participants. HIV-1 increases the risk of KS in those infected with KSHV by 100-fold. Declines in KSHV seroprevalence coincide with ART rollout and with improvements in educational standards and general hygiene.


Assuntos
Infecções por HIV , Soropositividade para HIV , HIV-1 , Herpesvirus Humano 8 , Sarcoma de Kaposi , Humanos , Masculino , População Africana , Antirretrovirais , Infecções por HIV/epidemiologia , Estudos Soroepidemiológicos , População Negra , África do Sul
20.
PLoS One ; 18(2): e0281916, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36795733

RESUMO

OBJECTIVE: In low- and middle-income countries (LMICs), advanced-stage diagnosis of breast cancer (BC) is common, and this contributes to poor survival. Understanding the determinants of the stage at diagnosis will aid in designing interventions to downstage disease and improve survival from BC in LMICs. METHODS: Within the South African Breast Cancers and HIV Outcomes (SABCHO) cohort, we examined factors affecting the stage at diagnosis of histologically confirmed invasive breast cancer at five tertiary hospitals in South Africa (SA). The stage was assessed clinically. To examine the associations of the modifiable health system, socio-economic/household and non-modifiable individual factors, hierarchical multivariable logistic regression with odds of late-stage at diagnosis (stage III-IV), was used. RESULTS: The majority (59%) of the included 3497 women were diagnosed with late-stage BC disease. The effect of health system-level factors on late-stage BC diagnosis was consistent and significant even when adjusted for both socio-economic- and individual-level factors. Women diagnosed in a tertiary hospital that predominantly serves a rural population were 3 times (OR = 2.89 (95% CI: 1.40-5.97) as likely to be associated with late-stage BC diagnosis when compared to those diagnosed at a hospital that predominantly serves an urban population. Taking more than 3 months from identifying the BC problem to the first health system entry (OR = 1.66 (95% CI: 1.38-2.00)), and having luminal B (OR = 1.49 (95% CI: 1.19-1.87)) or HER2-enriched (OR = 1.64 (95% CI: 1.16-2.32)) molecular subtype as compared to luminal A, were associated with a late-stage diagnosis. Whilst having a higher socio-economic level (a wealth index of 5) reduced the probability of late-stage BC at diagnosis, (OR = 0.64 (95% CI: 0.47-0.85)). CONCLUSION: Advanced-stage diagnosis of BC among women in SA who access health services through the public health system was associated with both modifiable health system-level factors and non-modifiable individual-level factors. These may be considered as elements in interventions to reduce the time to diagnosis of breast cancer in women.


Assuntos
Neoplasias da Mama , Infecções por HIV , Disparidades em Assistência à Saúde , Feminino , Humanos , População Negra , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/epidemiologia , Infecções por HIV/diagnóstico , Infecções por HIV/epidemiologia , Infecções por HIV/patologia , Estadiamento de Neoplasias , África do Sul/epidemiologia
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