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1.
Front Cell Infect Microbiol ; 13: 1270935, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37928187

RESUMEN

Kaposi sarcoma (KS), a multifocal vascular neoplasm frequently observed in HIV-positive individuals, primarily affects the skin, mucous membranes, visceral organs, and lymph nodes. KS is associated primarily with Kaposi sarcoma-associated herpesvirus (KSHV) infection. In this case report, we present a rare occurrence of co-infection and co-localization of KSHV and Epstein-Barr virus (EBV) in KS arising from the conjunctiva, which, to our knowledge, has not been reported previously. Immunohistochemistry (IHC), DNA polymerase chain reaction (PCR), and EBV-encoded RNA in situ hybridization (EBER-ISH) were utilized to demonstrate the presence of KSHV and EBV infection in the ocular KS lesion. Nearly all KSHV-positive cells displayed co-infection with EBV. In addition, the KS lesion revealed co-localization of KSHV Latency-Associated Nuclear Antigen (LANA) and EBV Epstein Barr virus Nuclear Antigen-1 (EBNA1) by multi-colored immunofluorescence staining with different anti-EBNA1 antibodies, indicating the possibility of interactions between these two gamma herpesviruses within the same lesion. Additional study is needed to determine whether EBV co-infection in KS is a common or an opportunistic event that might contribute to KS development and progression.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida , Coinfección , Infecciones por Virus de Epstein-Barr , Infecciones por Herpesviridae , Herpesvirus Humano 8 , Sarcoma de Kaposi , Humanos , Sarcoma de Kaposi/complicaciones , Sarcoma de Kaposi/epidemiología , Herpesvirus Humano 8/genética , Herpesvirus Humano 4 , Infecciones por Virus de Epstein-Barr/complicaciones , Coinfección/complicaciones , Síndrome de Inmunodeficiencia Adquirida/complicaciones
2.
Front Oncol ; 13: 1213426, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37476371

RESUMEN

Yes-associated protein-1 (YAP-1) is a Hippo system transcription factor, which serves as an oncogene in squamous cell carcinoma, and several solid tumors when the Hippo pathway is dysregulated. Yet, the activity of YAP-1 in ocular surface squamous neoplasia (OSSN) has not been determined. Here, we investigate the relationship between YAP-1 overexpression and OSSN. Using a cross-sectional study design, we recruited 227 OSSN patients from the University Teaching Hospitals in Lusaka, Zambia. Immunohistochemistry was used to assess YAP-1 protein overexpression in tumor tissue relative to surrounding benign squamous epithelium. OSSN patient samples (preinvasive, n = 62, 27% and invasive, n = 165, 73%) were studied. One hundred forty-nine invasive tumors contained adjacent preinvasive tissue, bringing the total number of preinvasive lesions examined to 211 (62 + 149). There was adjacent benign squamous epithelium in 50.2% (114/227) of OSSN samples. Nuclear YAP- 1 was significantly overexpressed in preinvasive (Fisher's (F): p <.0001, Monte Carlo (MC): p <.0001) and invasive (F: p <.0001, MC: p <.0001) OSSN in comparison to adjacent benign squamous epithelium when analyzed for basal keratinocyte positive count, staining intensity, expression pattern, and Immunostaining intensity-distribution index. YAP-1 expression did not differ between preinvasive and invasive OSSN (p >.05), keratinizing and non- keratinizing cancer (p >.05), or between T1/T2 and T3/T4 stages in invasive tumors (p >.05). However, grade 2 and 3 tumors had significantly stronger nucleus YAP-1 overexpression intensity than grade 1 tumors (F: p = .0078, MC: p = .0489). By immunohistochemistry, we identified significant overexpression (upregulation of YAP-1 protein expression) in preinvasive and invasive OSSN lesions compared to neighboring benign squamous epithelium. YAP-1 expression was significantly higher in poorly and moderately differentiated invasive squamous cancer than in well-differentiated carcinomas. Overexpression of YAP-1 within the margin of preinvasive and invasive OSSN, but not in the neighboring normal epithelium, indicates that it plays a role in the development and progression of OSSN.

3.
Afr J Lab Med ; 11(1): 1563, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35747556

RESUMEN

Background: Globally, women living with HIV have a higher risk of vulvar neoplasia than HIV-negative women. Vulvar neoplasia among women living with HIV has not previously been characterised in Zambia. Objective: This study determined the clinical and pathologic features of vulvar neoplasia among women living with HIV at the University Teaching Hospital, Lusaka, Zambia. Methods: We conducted a cross-sectional study of vulvar lesions among 53 women living with HIV who presented with vulvar lesions between July 2017 and February 2018. The study assessed clinical and histological characteristics and prevalence of high-risk human papillomavirus (HRHPV). Results: Twenty-one patients were diagnosed with vulvar squamous cell carcinoma (VSCC), 20 with usual vulvar intraepithelial neoplasm (uVIN), and the rest with either benign lesions or non-neoplastic lesions (NNL). Participants' mean age was 40 years. Patients with VSCC were significantly older than those with NNL (mean (s.d.): 43 (21) vs 33 (10), p = 0.004). The prevalence of HRHPV was 88.9% in VSCC patients and 100.0% in high-grade squamous intraepithelial lesion patients. HPV16 was the most common (52.6%) genotype. The clinical features of neoplasia were similar to those of NNL. Conclusion: VSCC was significantly more common among women aged ≥ 40 years. HRHPV in VSCC and high-grade squamous intraepithelial lesions was high. Women with vulvar lesions, especially those aged > 40 years, should be evaluated for vulvar cancer. Young girls should be vaccinated to prevent vulvar cancer.

4.
Front Oncol ; 12: 864066, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35494029

RESUMEN

Background: The etiopathogenesis of ocular surface squamous neoplasia (OSSN) is not fully understood. We assessed the frequency of oncogenic viruses in OSSN by immunohistochemistry (IHC) and polymerase chain reaction (PCR) for human papillomavirus (HPV), Epstein-Barr virus (EBV), Merkel cell polyomavirus (MCPyV), Kaposi sarcoma virus, and adenovirus. Cases from Zambia were prospectively enrolled using a cross-sectional study design between November 2017 and March 2020. Methods: Demographic and clinical data [age, sex, HIV status, antiretroviral therapy (ART) history, CD4 count, plasma viral load] and tumor biopsies were collected from 243 consenting patients. Tumor samples were bisected, and half was used for DNA isolation, while the other half was formalin fixed and paraffin embedded (FFPE) for histopathology analysis. The expressions of latent EBV nuclear antigen 1 (EBNA1), CDKN2A/p16INK4A (p16), and MCPyV large T-antigen (LT) were tested by IHC. Multiplex PCR was used to detect 16 HPV genotypes and four other DNA tumor viruses [Kaposi's sarcoma-associated herpesvirus (KSHV), EBV, MCPyV, and adenovirus]. Relationships between HIV status, viral DNA and protein expression, and tumor grades were determined by statistical analysis. Results: OSSN tumors from patients were 29.6% preinvasive and 70.4% invasive. Patients presented with unilateral tumors that were 70.4% late stage (T3/T4). OSSN patients were HIV positive (72.8%). IHC on 243 FFPE biopsies resulted in the detection of EBNA1 (EBV), p16 high-risk HPV (HR-HPV), and MCPyV LT expression in 89.0%, 4.9%, and 0.0%, respectively. EBNA1 was expressed in all grades of preinvasive [cornea-conjunctiva intraepithelial neoplasia (CIN)1, 100%; CIN2, 85.7%; CIN3, 95.8%; and carcinoma in situ (CIS), 83.8%] and in invasive (89.2%) OSSN. PCR on 178 samples detected EBV, HR-HPV, and MCPyV in 80.3%, 9.0%, and 13.5% of tumors, respectively. EBV was detected in all grades of preinvasive and invasive OSSN. EBV detection was associated with high HIV viral loads (p = 0.022). HR-HPV was detected in 0.0% CIN1, 0.0% CIN2, 5.6% CIN3, 13.0% CIS, and 7.0% invasive OSSN. Conclusions: Our findings of EBV DNA and EBNA1 protein in all the grades of preinvasive and especially invasive OSSN are consistent with a potential causal role for EBV in OSSN. A role of HPV in OSSN was not clearly established in this study.

5.
Int J Infect Dis ; 108: 363-369, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34146690

RESUMEN

BACKGROUND: Since information on the pathology of COVID-19 from sub-Saharan Africa (SSA) remains scarce, the objective of our study was to define the gross pathology and histological features of COVID-19. We report data from 29 whole-body autopsies of COVID-19 deaths occurring in hospitals in Lusaka, Zambia - the first large autopsy case series from Africa. METHODS: We performed a descriptive post-mortem examination study of inpatient COVID-19 related deaths at two hospitals in Lusaka, Zambia. Whole-body autopsies were conducted according to Standard Operating Procedures. Gross and histopathological examinations of all organs were performed. Patient demographics, history, co-morbidities, autopsy gross and microscopic findings, and cause(s) of death were recorded and analyzed using STATA version 14. Variables were grouped and presented as frequencies and percentages. FINDINGS: Autopsies were performed on 29 decedents (mean age = 44 ± 15.8years; age range = 19-82; 17/29 [58.8%] males). 22/29 [75.9%] cases were <55 years of age. A spectrum of pathological manifestations of COVID-19 were seen in all organs. The commonest causes of death were pulmonary thromboembolism (13/29, 45%), Diffuse Alveolar Damage (9/29, 31%), and COVID-19 pneumonia (7/29, 25%). 22/29 (76%) had co-morbidities. Common co-morbidities included HIV (8/29, 28%), Hypertension (6/29, 20%) Tuberculosis (3/29, 10%), Diabetes (3/29, 10%). CONCLUSIONS: A spectrum of gross anatomical and histopathological findings are seen in COVID-19 deaths in hospitalized decedents. These appear broadly similar to those reported from China, Europe and USA. Differences include a younger age group, and co-morbidities of HIV and TB co-infection which require further investigation.


Asunto(s)
COVID-19 , Adulto , Anciano , Anciano de 80 o más Años , Autopsia , Hospitales , Humanos , Pacientes Internos , Pulmón , Masculino , Persona de Mediana Edad , SARS-CoV-2 , Adulto Joven , Zambia/epidemiología
6.
Ocul Oncol Pathol ; 7(2): 108-120, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33869164

RESUMEN

AIM: This study aimed to characterize the clinical and pathologic presentation of ocular surface tumors (OSTs) and to more precisely differentiate the grades of ocular surface squamous neoplasia (OSSN) and benign lesions among Zambians. METHODS: Two-hundred sixty-five Zambian patients presenting with ocular surface growths, suspicious for OSSN, were recruited between November 2017 and November 2019 to a cross-sectional study to investigate their lesions. Sociodemographic data were collected, HIV infection status and vision tests were performed, and lesions were measured and documented. Lesions >2 mm in diameter were excised and sent for pathology analysis. In addition to the biopsies, tears, blood, and buccal swabs were collected. CD4+ T-cell counts were measured by flow cytometry. Lesions were classified according to the WHO guidelines. χ2 and bivariate correlations were used to analyze variable associations and strengths with phi/Cramer's V and correlation coefficients, respectively. Binary logistics was used to adjust for covariance. RESULTS: In this study, 68.3% of the participants were found to be HIV positive. The most frequent diagnoses were invasive OSSN (45.3%), preinvasive OSSN (29.1%), and pterygium (22.6%). Invasive OSSN comprised keratinizing squamous cell carcinoma (SCC) (87.5%), basaloid SCC (3.3%), and spindle cell carcinoma (3.3%). Unusual carcinomas, not described previously, included hybrid SCC (5.0%) and acantholytic SCC (0.8%). Invasive OSSN had advanced tumor (T3/T4) staging (93.3%) at diagnosis. Lymphadenopathy was rare (2.3%), and metastasis was absent. Patients were mostly female (59.2%). Median age was 36 (interquartile ranges 33-41) years (ranges 18-81). Patients with invasive OSSN were more likely to present with pain (p = 0.007), redness (p = 0.034), excessive tearing (p = 0.0001), discharge (p = 0.011), bleeding (p = 0.007), reduced vision (p = 0.0001), fungating lesion (p = 0.001), and blindness (p = 0.005); location at temporal limbus (p = 0.0001), inferior limbus (p = 0.0001), or circumlimbal (p = 0.001); and extension to cornea (p = 0.006) and forniceal palpebral conjunctiva (p = 0.001). Invasive OSSN was associated with any smoking habit and alcohol consumption (p = 0.04 and 0.03, respectively). HIV positivity was strongly associated with OSSN (74.6% OSSN vs. 49.3% benign lesions; p = 0.0001; phi: 0.237 [p = 0.0001]). CONCLUSION: OSTs are very common in Zambia and are strongly associated with HIV coinfection. Patients with OSSN were more likely to be HIV positive than those with pterygia. Despite the commonality of OSTs in sub-Saharan Africa, these cancers have historically been poorly characterized.

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