Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 31
Filtrar
1.
Nucleic Acids Res ; 51(16): 8643-8662, 2023 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-37439356

RESUMO

Environmental agents like ionizing radiation (IR) and chemotherapeutic drugs can cause severe damage to the DNA, often in the form of double-strand breaks (DSBs). Remaining unrepaired, DSBs can lead to chromosomal rearrangements, and cell death. One major error-free pathway to repair DSBs is homologous recombination repair (HRR). Tousled-like kinase 1 (TLK1), a Ser/Thr kinase that regulates the DNA damage checkpoint, has been found to interact with RAD54, a central DNA translocase in HRR. To determine how TLK1 regulates RAD54, we inhibited or depleted TLK1 and tested how this impacts HRR in human cells using a ISce-I-GR-DsRed fused reporter endonuclease. Our results show that TLK1 phosphorylates RAD54 at three threonines (T41, T59 and T700), two of which are located within its N-terminal domain (NTD) and one is located within its C-terminal domain (CTD). Phosphorylation at both T41 and T59 supports HRR and protects cells from DNA DSB damage. In contrast, phosphorylation of T700 leads to impaired HRR and engenders no protection to cells from cytotoxicity and rather results in repair delay. Further, our work enlightens the effect of RAD54-T700 (RAD54-CTD) phosphorylation by TLK1 in mammalian system and reveals a new site of interaction with RAD51.


Assuntos
Reparo do DNA , Reparo de DNA por Recombinação , Animais , Humanos , Fosforilação , Dano ao DNA , DNA/metabolismo , Rad51 Recombinase/metabolismo , Recombinação Homóloga , Mamíferos/metabolismo , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo
2.
Virol J ; 20(1): 55, 2023 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-36998012

RESUMO

When viruses like SARS-CoV-2 infect cells, they reprogram the repertoire of cellular and viral transcripts that are being translated to optimize their strategy of replication, often targeting host translation initiation factors, particularly eIF4F complex consisting of eIF4E, eIF4G and eIF4A. A proteomic analysis of SARS-CoV-2/human proteins interaction revealed viral Nsp2 and initiation factor eIF4E2, but a role of Nsp2 in regulating translation is still controversial. HEK293T cells stably expressing Nsp2 were tested for protein synthesis rates of synthetic and endogenous mRNAs known to be translated via cap- or IRES-dependent mechanism under normal and hypoxic conditions. Both cap- and IRES-dependent translation were increased in Nsp2-expressing cells under normal and hypoxic conditions, especially mRNAs that require high levels of eIF4F. This could be exploited by the virus to maintain high translation rates of both viral and cellular proteins, particularly in hypoxic conditions as may arise in SARS-CoV-2 patients with poor lung functioning.


Assuntos
COVID-19 , Biossíntese de Proteínas , SARS-CoV-2 , Proteínas não Estruturais Virais , SARS-CoV-2/metabolismo , Células HEK293 , Humanos , Proteínas não Estruturais Virais/análise , Proteínas não Estruturais Virais/isolamento & purificação , Proteínas não Estruturais Virais/metabolismo , Fator de Iniciação 4E em Eucariotos/isolamento & purificação , Fator de Iniciação 4E em Eucariotos/metabolismo , Iniciação Traducional da Cadeia Peptídica , COVID-19/metabolismo , COVID-19/virologia
3.
Int J Mol Sci ; 24(17)2023 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-37686173

RESUMO

DNA damage repair lies at the core of all cells' survival strategy, including the survival strategy of cancerous cells. Therefore, targeting such repair mechanisms forms the major goal of cancer therapeutics. The mechanism of DNA repair has been tousled with the discovery of multiple kinases. Recent studies on tousled-like kinases have brought significant clarity on the effectors of these kinases which stand to regulate DSB repair. In addition to their well-established role in DDR and cell cycle checkpoint mediation after DNA damage or inhibitors of replication, evidence of their suspected involvement in the actual DSB repair process has more recently been strengthened by the important finding that TLK1 phosphorylates RAD54 and regulates some of its activities in HRR and localization in the cell. Earlier findings of its regulation of RAD9 during checkpoint deactivation, as well as defined steps during NHEJ end processing, were earlier hints of its broadly important involvement in DSB repair. All this has opened up new avenues to target cancer cells in combination therapy with genotoxins and TLK inhibitors.


Assuntos
Dano ao DNA , Reparo do DNA , Proteínas Serina-Treonina Quinases , Sobrevivência Celular , Terapia Combinada , Dano ao DNA/genética , Reparo do DNA/genética , Mutagênicos , Proteínas Serina-Treonina Quinases/metabolismo
4.
Int J Gynecol Pathol ; 39(4): 384-390, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32515923

RESUMO

Interpretation of histopathology of cervical premalignant lesions suffers from marked interobserver variability due to its subjective nature. We aimed to evaluate the usefulness of the biomarkers p16 and Ki-67 in improving the diagnostic accuracy of cervical histopathology and assess the correlation between p16 expression and human papillomavirus test in different grades of cervical intraepithelial neoplasia (CIN). Cervical tissue specimens with a diagnosis of CIN 1 or worse (CIN 1+) on hematoxylin and eosin staining were selected for immunohistochemistry (IHC) staining for p16 and Ki-67. The IHC slides were examined by a gynecologic pathologist along with a review of hematoxylin and eosin slides. The review histopathology diagnosis was used to correlate with the IHC results. We observed that the proportion of women with overexpression of p16 increased with increasing histologic severity: 0% in women with normal histology; 33.3% in women with CIN 1; 58.1% in women with CIN 2; and 73.8% in women with CIN 3. Among the human papillomavirus-positive women, 76.3% (58/76) women with CIN 2/CIN 3 expressed p16, and only 8.9% (4/45) women with normal histopathology or CIN 1 expressed the same. A combination of p16 positivity and abnormal expression of Ki-67 beyond the lower third of the epithelium was observed in 0% of normal/CIN 1 and 60.5% (40/66) of CIN 3 detected on routine histopathology. We concluded that dual staining could be used as an adjunctive test to improve the diagnostic accuracy of histopathology. In addition, p16/Ki-67 IHC has a role in guiding management decisions in cases with discordant colposcopy and histopathology diagnoses.


Assuntos
Biomarcadores Tumorais/metabolismo , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Antígeno Ki-67/metabolismo , Displasia do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/diagnóstico , Adulto , Colposcopia , Feminino , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Variações Dependentes do Observador , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/patologia , Displasia do Colo do Útero/metabolismo , Displasia do Colo do Útero/patologia
5.
Int J Cancer ; 145(4): 1055-1067, 2019 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-30737777

RESUMO

Standard therapy for advanced Prostate Cancer (PCa) consists of antiandrogens, which provide respite from disease progression, but ultimately fail resulting in the incurable phase of the disease: mCRPC. Targeting PCa cells before their progression to mCRPC would greatly improve the outcome. Combination therapy targeting the DNA Damage Response (DDR) has been limited by general toxicity, and a goal of clinical trials is how to target the DDR more specifically. We now show that androgen deprivation therapy (ADT) of LNCaP cells results in increased expression of TLK1B, a key kinase upstream of NEK1 and ATR and mediating the DDR that typically results in a temporary cell cycle arrest of androgen responsive PCa cells. Following DNA damage, addition of the TLK specific inhibitor, thioridazine (THD), impairs ATR and Chk1 activation, establishing the existence of a ADT > TLK1 > NEK1 > ATR > Chk1, DDR pathway, while its abrogation leads to apoptosis. Treatment with THD suppressed the outgrowth of androgen-independent (AI) colonies of LNCaP and TRAMP-C2 cells cultured with bicalutamide. Moreover, THD significantly inhibited the growth of several PCa cells in vitro (including AI lines). Administration of THD or bicalutamide was not effective at inhibiting long-term tumor growth of LNCaP xenografts. In contrast, combination therapy remarkably inhibited tumor growth via bypass of the DDR. Moreover, xenografts of LNCaP cells overexpressing a NEK1-T141A mutant were durably suppressed with bicalutamide. Collectively, these results suggest that targeting the TLK1/NEK1 axis might be a novel therapy for PCa in combination with standard of care (ADT).


Assuntos
Androgênios/genética , Proliferação de Células/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Quinase 1 Relacionada a NIMA/genética , Neoplasias da Próstata/tratamento farmacológico , Proteínas Serina-Treonina Quinases/genética , Tioridazina/farmacologia , Antagonistas de Androgênios/farmacologia , Animais , Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Neoplasias da Próstata/genética , Receptores Androgênicos/genética
6.
Int J Cancer ; 140(8): 1850-1859, 2017 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-28108997

RESUMO

Infection with high-risk human papillomavirus (HR-HPV) is transient and clears on its own in majority of the women. Only a few women who have persistent infection may finally develop cervical intraepithelial neoplasia (CIN) or cervical cancer in later years. The risk of progression in the HR-HPV-positive women with normal cervix or low-grade lesion on colposcopy and histopathology at baseline is less studied. We performed a longitudinal study on 650 HR-HPV-positive women with colposcopy and/or histopathology-proved normal or CIN1 diagnosis at baseline to assess the cumulative risk of development of high-grade CIN. After a mean follow-up of 2.1 person years of observation (PYO) (range 0.1-5.1), the cumulative incidence of CIN2+ (6.4%; 3.0/100 PYO) was significantly higher in women who had persistent HR-HPV infection compared to those who cleared the infection (adjusted HR 6.28; 95% CI 2.87-13.73). The risk of viral persistence in women aged 50-60 years was two times higher compared to women aged 40-49 years and three times higher compared to women aged 30-39 years. The probability of having persistent infection increased progressively with higher viral load at baseline (adjusted HR 3.29, 95% CI 2.21-4.90 for RLU ≥100; adjusted HR 2.69, 95% CI 1.71-4.22 for RLU 10-100). Women with increasing viral load at follow-up had four times higher risk of developing CIN2 or worse lesions as compared to those with decreasing load (20.9% vs 4.8%; p < 0.001). In the context of developing countries where cytology or genotyping triaging is not feasible, colposcopy referral of HR-HPV-positive women with advancing age, viral persistence, and increasing viral load may be considered.


Assuntos
Colo do Útero/virologia , Papillomaviridae/patogenicidade , Infecções por Papillomavirus/epidemiologia , Displasia do Colo do Útero/patologia , Adulto , Colo do Útero/patologia , Colposcopia , Feminino , Genótipo , Humanos , Estudos Longitudinais , Pessoa de Meia-Idade , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/diagnóstico , Infecções por Papillomavirus/patologia , Infecções por Papillomavirus/virologia , Gravidez , Fatores de Risco , Esfregaço Vaginal , Carga Viral , Displasia do Colo do Útero/diagnóstico , Displasia do Colo do Útero/epidemiologia , Displasia do Colo do Útero/virologia
7.
Cancer Causes Control ; 27(3): 351-8, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26712612

RESUMO

PURPOSE: A demonstration project was conducted to assess feasibility of implementing HPV detection-based cervical cancer screening in primary care settings in India and to generate local evidence on feasibility and effectiveness of HPV detection in primary screening. METHODS: The project was implemented by setting up screening clinics at primary health centers. Eligible women were screened by HPV DNA test (Hybrid capture 2). All samples were processed and tested in a single laboratory. Colposcopy services were provided to screen-positive women at the same community clinics. Project utilized services of community health workers for community mobilization, recall of screen-positive and disease-positive women. Women with ≥CIN2 diagnosis were treated at tertiary hospital. RESULTS: Totally, 44,110 women were screened and HPV positivity was 4.7 %. Compliance to recall of HC2-positive women for colposcopy was 78 %. Detection rate of CIN3+ by HPV test was 3.9/1,000 women. Compliance of women to treatment was 80.1 %. However, compliance of HPV-positive women for follow-up at 1 year was poor (23.2 %). Concurrent use of VIA to screen the women did not have any advantage but increased number of unnecessary colposcopies and biopsies. CONCLUSIONS: Our project demonstrated that it was possible to implement HPV detection-based screening using existing primary healthcare infrastructure. Performing colposcopy at primary setting is feasible, improves compliance and reduces over-treatment. In settings with low to moderately high HPV prevalence, direct referral of HPV-positive women is advisable. Community health workers can be effectively used for recalling the positive women.


Assuntos
Infecções por Papillomavirus/diagnóstico , Displasia do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/diagnóstico , Adulto , Biópsia , Colposcopia , Detecção Precoce de Câncer , Feminino , Humanos , Índia , Programas de Rastreamento/métodos , Pessoa de Meia-Idade , Infecções por Papillomavirus/virologia , Neoplasias do Colo do Útero/virologia , Displasia do Colo do Útero/virologia
8.
Cancer Causes Control ; 27(10): 1253-9, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27581249

RESUMO

PURPOSE: Many limited-resourced countries have either introduced cervical cancer screening programs or are contemplating to do so using visual inspection after acetic acid application (VIA) or human papillomavirus (HPV) detection tests. Both tests have high false-positivity and a suitable triaging strategy is required. Colposcopy triaging is not practicable in most resource-limited settings due to several reasons. We evaluated a portable, battery-operated, magnifying device (GynocularTM) to triage screen positive women in community setting in India. METHODS: Women positive on VIA or oncogenic HPV test were examined with Gynocular by clinicians in primary health clinics. Findings were documented using the International Federation for Cervical Pathology and Colposcopy (IFCPC) terminology. Swede score was also calculated. Biopsy was performed irrespective of Gynocular findings. The accuracy of Gynocular to detect high-grade lesions or cancer (HSIL+) was estimated. The suitability of Gynocular to correctly triage screen positive cases for immediate ablative treatment was also evaluated by creating simulated scenarios. RESULTS: Sensitivity and specificity of Gynocular were 96.4 and 47.1 %, respectively, to detect HSIL + at the threshold of IFCPC grade 1 findings. Increasing threshold to grade 2 changed sensitivity and specificity to 92.9 and 94.1 %, respectively. Optimum combination of sensitivity and specificity as determined by the receiver operating curve analysis was at the cut-off Swede score of 5. Triaging of VIA/HPV positive women to treatment using grade 2 criteria would have resulted in modest overtreatment and missing of very few high-grade lesions. CONCLUSION: Gynocular can be used as an effective triaging device for VIA/HPV positive women.


Assuntos
Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/diagnóstico , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/virologia , Ácido Acético , Adulto , Biópsia/métodos , Colposcopia , Detecção Precoce de Câncer/métodos , Feminino , Humanos , Índia , Pessoa de Meia-Idade , Infecções por Papillomavirus/patologia , Infecções por Papillomavirus/virologia , Gravidez , População Rural , Triagem , Neoplasias do Colo do Útero/patologia
9.
J Med Virol ; 88(7): 1271-8, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26693677

RESUMO

The sensitivity of E6/E7 mRNA-based Aptima HPV test (AHPV; Hologic, Inc.) for detection of cervical cancer has been reported based on only a small number of cases. We determined the sensitivity of AHPV in comparison with the DNA-based Hybrid Capture 2 HPV test (HC2; Qiagen) for the detection of oncogenic HPV in a large number of cervical cancers at the time of diagnosis using cervical samples obtained in ThinPrep (Hologic). Samples yielding discordant results were genotyped using Linear Array assay (LA; Roche). Of 396 cases tested, AHPV detected 377 (sensitivity, 95.2%; 95%CI: 93.1-97.3), and HC2 376 (sensitivity, 94.9%; 95%CI: 92.7-97.1) with an agreement of 97.2% (kappa 0.7; 95%CI: 0.54-0.87). Among six AHPV+/HC2- cases, LA identified oncogenic HPV types in four including a type 73 and was negative in two. Among five AHPV-/HC2+ cases, LA detected oncogenic HPV types in two including a type 73 and was negative in three. Of 14 AHPV-/HC2- cases, 13 were genotyped. LA detected oncogenic HPV types in six, non-oncogenic types in three, and was negative in four. This is the largest study to demonstrate the sensitivity of AHPV for the detection of invasive cervical cancer and this assay showed equal sensitivity to HC2.


Assuntos
DNA Viral/isolamento & purificação , Testes de DNA para Papilomavírus Humano/métodos , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/virologia , Displasia do Colo do Útero/virologia , Neoplasias do Colo do Útero/diagnóstico , Adulto , Idoso , Biópsia , Colo do Útero/patologia , Colo do Útero/virologia , Detecção Precoce de Câncer , Feminino , Genótipo , Humanos , Pessoa de Meia-Idade , Técnicas de Diagnóstico Molecular/métodos , Papillomaviridae/classificação , Papillomaviridae/genética , RNA Mensageiro , Kit de Reagentes para Diagnóstico , Sensibilidade e Especificidade , Neoplasias do Colo do Útero/virologia , Displasia do Colo do Útero/diagnóstico
10.
Int J Gynecol Pathol ; 35(3): 269-74, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26598985

RESUMO

Low epithelial thickness has been identified as the cause for nonvisualization of high-grade cervical intraepithelial neoplasia (CIN) on colposcopy in an earlier study. Multiple random biopsies are recommended by some authors to detect these "thin" CIN lesions in absence of colposcopic abnormalities. The present study was conducted to evaluate the correlation between the severity of colposcopic impression and the thickness of the epithelium so that the results of previous study could be validated. The cross-sectional study examined 209 histopathology slides with normal, human papillomavirus, or CIN diagnosis from a population-based study. Average epithelial thickness was measured by obtaining mean of the thicknesses at thinnest and thickest areas. Average thickness of dysplastic layer was also measured. These values were correlated with age, human papillomavirus status, colposcopic appearance and histopathology. Mean epithelial thicknesses were 212.8 µm for normal (N=28), 297.3 µm for human papillomavirus changes (N=48), 245.3 µm for CIN1 (N=46), 191.4 µm for CIN2 (N=50), and 218.5 µm for CIN3 (N=37). Within each histologic category, no correlation was observed between epithelial thickness and severity of colposcopic appearance. Mean epithelial thickness of CIN1/CIN2 lesions with normal colposcopy was more than that of CIN1/CIN2 lesions with high-grade appearance on colposcopy. Thickness of CIN3 lesions with high-grade abnormalities was higher than those without visible colposcopic abnormality but the difference was not statistically significant. Thickness of dysplasia increased with higher grades of CIN but did not have any relation to colposcopic appearance. Colposcopic appearance does not depend on the thickness of the epithelium affected by CIN. False-negative colposcopy in presence of high-grade CIN is likely due to failure of detecting small or predominantly endocervical lesions rather than "thin" CIN.


Assuntos
Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/diagnóstico , Displasia do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/diagnóstico , Adulto , Biópsia , Colo do Útero/patologia , Colposcopia , Estudos Transversais , Feminino , Humanos , Pessoa de Meia-Idade , Infecções por Papillomavirus/patologia , Gravidez , Manejo de Espécimes , Neoplasias do Colo do Útero/patologia , Displasia do Colo do Útero/patologia
11.
Aust N Z J Obstet Gynaecol ; 54(6): 570-5, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25476810

RESUMO

OBJECTIVE: This population-based study was conducted to evaluate the performance of colposcopy to assess women with positive visual inspection with acetic acid (VIA) and/or human papillomavirus (HPV) tests. MATERIALS AND METHODS: A total of 30,773 women were screened by VIA and oncogenic HPV test. Hybrid capture 2 was used for oncogenic HPV detection. All VIA- and/or HPV-positive women and 8.7% test-negative women had the colposcopy. International Federation of Cervical Pathology & Colposcopy (IFCPC) 2011 nomenclature was used for colposcopic classification of abnormalities. All women with grade 1 or worse lesions had punch biopsies. Biopsies were also obtained from HPV-positive women with normal colposcopy. RESULTS: Colposcopy and satisfactory biopsy reports were available for total 2466 women. The overall strength of agreement between colposcopy and histologic classification of cervical neoplasias was poor (kappa = 0.17). Agreement was better when colposcopy was performed on HPV-positive women compared to VIA-positive women. Sensitivity of colposcopy to detect high-grade squamous intraepithelial lesions (HSIL) at referral threshold of grade 1 abnormality was 84.8% after correction of verification bias. Colposcopy was most inaccurate in identifying non-neoplastic conditions often encountered in VIA- and/or HPV-positive women. In 68.8% women with normal histology, colposcopic impression was grade 1 and above. Overestimation of disease severity on colposcopy was more common in VIA-positive women. Colposcopy also underestimated severity of disease in 52.6% of women with HSIL diagnosis on biopsy. CONCLUSIONS: Colposcopy performed well in the overall detection of cervical neoplasias, though its capability for accurate categorisation of degree of abnormality was poor.


Assuntos
Colo do Útero/patologia , Colposcopia , Detecção Precoce de Câncer , Lesões Intraepiteliais Escamosas Cervicais/patologia , Neoplasias do Colo do Útero/patologia , Ácido Acético , Adulto , Biópsia , Reações Falso-Positivas , Feminino , Humanos , Indicadores e Reagentes , Pessoa de Meia-Idade , Gradação de Tumores , Papillomaviridae/isolamento & purificação , Valor Preditivo dos Testes
12.
Int J Gynecol Pathol ; 32(5): 509-15, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23896715

RESUMO

Visual inspection with acetic acid (VIA) and human papillomavirus detection have sensitivity higher than cytology but lower specificity. The high false-positive rate of either test poses a challenge to the colposcopists who obtain biopsies from the innocuous changes and to the pathologists who have to interpret large numbers of specimens that are either normal or have low-grade abnormalities. Interobserver variation in histopathologic interpretations of cervical punch biopsy specimens is high, specially for the lower-grade abnormalities. Use of the modified Bethesda system to report histology in place of the cervical intraepithelial neoplasia (CIN) system has the potential to reduce such variability as there are fewer categories. The present study aimed to assess the interobserver agreement to interpret cervical punch biopsies when both pathologists followed the modified Bethesda classification system and also when one pathologist followed the modified Bethesda classification system and the other followed the CIN classification system. Colposcopy-directed punch biopsies were obtained from VIA and/or Hybrid Capture 2-positive women. The Institute pathologist interpreted the slides using the CIN system. Blinded review was done by 2 external pathologists who independently interpreted cervical punch biopsies using the Bethesda system. The Institute pathologist's diagnoses based on CIN system were converted post hoc into categories belonging to the Bethesda system for comparison. The overall agreement was poor (κ=0.36). The lowest agreement was observed in the low-grade squamous intraepithelial lesion category (κ=0.23) and the highest in the squamous cell carcinoma category (κ=0.76). The agreement between the reviewers, both of whom used the Bethesda system, was substantial.


Assuntos
Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/patologia , Displasia do Colo do Útero/patologia , Neoplasias do Colo do Útero/patologia , Ácido Acético , Adulto , Biópsia , Colo do Útero/patologia , Colposcopia , DNA Viral/genética , Reações Falso-Positivas , Feminino , Exame Ginecológico , Humanos , Índia , Pessoa de Meia-Idade , Variações Dependentes do Observador , Infecções por Papillomavirus/virologia , Gravidez , Sensibilidade e Especificidade
13.
World J Gastrointest Oncol ; 15(12): 2053-2063, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38173427

RESUMO

Gall bladder cancer (GBC) is becoming a very devastating form of hepatobiliary cancer in India. Every year new cases of GBC are quite high in India. Despite recent advanced multimodality treatment options, the survival of GBC patients is very low. If the disease is diagnosed at the advanced stage (with local nodal metastasis or distant metastasis) or surgical resection is inoperable, the prognosis of those patients is very poor. So, perspectives of targeted therapy are being taken. Targeted therapy includes hormone therapy, proteasome inhibitors, signal transduction and apoptosis inhibitors, angiogenesis inhibitors, and immunotherapeutic agents. One such signal transduction inhibitor is the specific short interfering RNA (siRNA) or short hairpin RNA (shRNA). For developing siRNA-mediated therapy shRNA, although several preclinical studies to evaluate the efficacy of these key molecules have been performed using gall bladder cells, many more clinical trials are required. To date, many such genes have been identified. This review will discuss the recently identified genes associated with GBC and those that have implications in its treatment by siRNA or shRNA.

14.
Biomedicines ; 11(3)2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36979713

RESUMO

The key to preventing mCRPC progression is understanding how androgen-dependent PCa cells progress to independence and modify their transcriptional repertoire accordingly. We recently identified a novel axis of the Hippo pathway characterized by the sequential kinase cascade induced by androgen deprivation, AR->TLK1B>NEK1>pYAP1-Y407, leading to CRPC adaptation. Phosphorylation of YAP1-Y407 increases upon ADT or induction of DNA damage, correlated with the known increase in NEK1 expression/activity, and this is suppressed in the Y407F mutant. Dominant expression of YAP1-Y407F in Hek293 cells reprograms the YAP1-mediated transcriptome to reduce TEAD- and p73-regulated gene expression and mediates sensitivity to MMC. NEK1 haploinsufficient TRAMP mice display reduced YAP1 expression and, if castrated, fail to progress to overt prostate carcinomas, even while displaying reduced E-Cadherin (E-Cad) expression in hyperplastic ductules. YAP1 overexpression, but not the Y407F mutant, transforms LNCaP cells to androgen-independent growth with a mesenchymal morphology. Immunohistochemical examination of prostate cancer biopsies revealed that the pYAP1-Y407 nuclear signal is low in samples of low-grade cancer but elevated in high GS specimens. We also found that J54, a pharmacological inhibitor of the TLK1>NEK1>YAP1 nexus leading to degradation of YAP1, can suppress the transcriptional reprogramming of LNCaP cells to androgen-independent growth and EMT progression, even when YAP1-WT is overexpressed.

15.
Pathophysiology ; 28(3): 339-354, 2021 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-35366279

RESUMO

Prostate cancer (PCa) progression is characterized by the emergence of resistance to androgen deprivation therapy (ADT). AKT/PKB has been directly implicated in PCa progression, often due to the loss of PTEN and activation of PI3K>PDK1>AKT signaling. However, the regulatory network of AKT remains incompletely defined. Here, we describe the functional significance of AKTIP in PCa cell growth. AKTIP, identified in an interactome analysis as a substrate of TLK1B (that itself is elevated following ADT), enhances the association of AKT with PDK1 and its phosphorylation at T308 and S473. The interaction between TLK1 and AKTIP led to AKTIP phosphorylation at T22 and S237. The inactivation of TLK1 led to reduced AKT phosphorylation, which was potentiated with AKTIP knockdown. The TLK1 inhibitor J54 inhibited the growth of the LNCaP cells attributed to reduced AKT activation. However, LNCaP cells that expressed constitutively active, membrane-enriched Myr-AKT (which is expected to be active, even in the absence of AKTIP) were also growth-inhibited with J54. This suggested that other pathways (like TLK1>NEK1>YAP) regulating proliferation are also suppressed and can mediate growth inhibition, despite compensation by Myr-AKT. Nonetheless, further investigation of the potential role of TLK1>AKTIP>AKT in suppressing apoptosis, and conversely its reversal with J54, is warranted.

16.
Drug Alcohol Depend ; 229(Pt A): 109101, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34628096

RESUMO

BACKGROUND: Although fentanyl has gained widespread prominence, there remains a lack of knowledge on this opioid synthetic agonist, particularly related to sex effects. Therefore, we conducted behavioral tests in female and male rats to measure drug abuse-related responses to fentanyl hypothesizing sex-specific responses. METHODS: Using female and male rats, we measured the effects of acute or repeated administration of fentanyl (20 µg/kg) on locomotor activity (LMA) and behavioral sensitization in an open field test. We further measured contextual-reward and associated locomotor activity during training in a conditioned place preference (CPP) paradigm using a low (4 µg/kg) or high (16 µg/kg) dose of fentanyl. Vaginal lavage samples were collected from female rats in the CPP study, and the estrous phase was determined based on the cytological characterization. RESULTS: Female, but not male, rats showed elevated LMA in response to acute fentanyl and behavioral sensitization to repeated administration of fentanyl. Fentanyl produced significant CPP in both sexes, but it was more potent in males. Finally, our secondary investigation of the estrous cycle on fentanyl-CPP suggests that non-estrus phases, likely reflecting high estradiol, may predict the degree of fentanyl preference in females. CONCLUSIONS: Fentanyl was more potent and/or effective to produce LMA and LMA sensitization in females but more potent to produce CPP in males. Furthermore, the role of sex in fentanyl responses varied across endpoints, and sex differences in LMA were not predictive of sex differences in CPP.


Assuntos
Fentanila , Recompensa , Animais , Condicionamento Clássico , Feminino , Fentanila/farmacologia , Locomoção , Masculino , Ratos
17.
Science ; 373(6552): 321-327, 2021 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-34437150

RESUMO

Living tissue uses stress-accumulated electrical charge to close wounds. Self-repairing synthetic materials, which are typically soft and amorphous, usually require external stimuli, prolonged physical contact, and long healing times. We overcome many of these limitations in piezoelectric bipyrazole organic crystals, which recombine following mechanical fracture without any external direction, autonomously self-healing in milliseconds with crystallographic precision. Kelvin probe force microscopy, birefringence experiments, and atomic-resolution structural studies reveal that these noncentrosymmetric crystals, with a combination of hydrogen bonds and dispersive interactions, develop large stress-induced opposite electrical charges on fracture surfaces, prompting an electrostatically driven precise recombination of the pieces via diffusionless self-healing.

18.
Cancers (Basel) ; 12(12)2020 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-33297404

RESUMO

Most prostate cancer (PCa) deaths result from progressive failure in standard androgen deprivation therapy (ADT), leading to metastatic castration-resistant PCa (mCRPC); however, the mechanism and key players leading to this are not fully understood. While studying the role of tousled-like kinase 1 (TLK1) and never in mitosis gene A (NIMA)-related kinase 1 (NEK1) in a DNA damage response (DDR)-mediated cell cycle arrest in LNCaP cells treated with bicalutamide, we uncovered that overexpression of wt-NEK1 resulted in a rapid conversion to androgen-independent (AI) growth, analogous to what has been observed when YAP1 is overexpressed. We now report that overexpression of wt-NEK1 results in accumulation of YAP1, suggesting the existence of a TLK1>NEK1>YAP1 axis that leads to adaptation to AI growth. Further, YAP1 is co-immunoprecipitated with NEK1. Importantly, NEK1 was able to phosphorylate YAP1 on six residues in vitro, which we believe are important for stabilization of the protein, possibly by increasing its interaction with transcriptional partners. In fact, knockout (KO) of NEK1 in NT1 PCa cells resulted in a parallel decrease of YAP1 level and reduced expression of typical YAP-regulated target genes. In terms of cancer potential implications, the expression of NEK1 and YAP1 proteins was found to be increased and correlated in several cancers. These include PCa stages according to Gleason score, head and neck squamous cell carcinoma, and glioblastoma, suggesting that this co-regulation is imparted by increased YAP1 stability when NEK1 is overexpressed or activated by TLK1, and not through transcriptional co-expression. We propose that the TLK1>NEK1>YAP1 axis is a key determinant for cancer progression, particularly during the process of androgen-sensitive to -independent conversion during progression to mCRPC.

19.
Asian Pac J Cancer Prev ; 21(5): 1391-1398, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32458647

RESUMO

BACKGROUND: The prospective randomized study aimed to compare the safety, acceptability and efficacy of thermal ablation (TA) to that of cryotherapy in screen and treat setting. METHODS: The participants were recruited prospectively in a community-based screening clinic in India. Women positive on visual inspection with acetic acid (VIA) test and/or Human Papillomavirus (HPV) test were assessed for eligibility for ablative treatment. Total 286 eligible women were randomized to receive either cryotherapy (N=150) or TA (N=136) performed by health workers. Colposcopy and cervical biopsy were performed on all, prior to treatment. Post-treatment follow-up was after one year with colposcopy and biopsy. RESULTS: Both the treatment methods had high acceptability. Significantly higher proportion of women treated by cryotherapy reported pain compared to women treated by TA, though intensity was mild in vast majority of them. Approximately 30% of women in both arms had histologic abnormalities, mainly CIN 1, and among those who attended follow-up 74.1% and 81.0% didn't have any CIN after cryotherapy and TA respectively. CONCLUSION: TA is as acceptable and safe as cryotherapy in screen and treat setting. TA has the logistic advantages for the low-resourced settings as the machines are more portable, do not require costly refrigerant gas and battery-driven models are available. The cure rates for CIN 1+ lesions in our study were comparable between cryotherapy and TA.


Assuntos
Técnicas de Ablação/métodos , Crioterapia/métodos , Detecção Precoce de Câncer/métodos , Hipertermia Induzida/métodos , Infecções por Papillomavirus/complicações , Displasia do Colo do Útero/terapia , Neoplasias do Colo do Útero/terapia , Adulto , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Papillomaviridae/isolamento & purificação , Segurança do Paciente , Prognóstico , Estudos Prospectivos , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/virologia , Displasia do Colo do Útero/diagnóstico , Displasia do Colo do Útero/patologia , Displasia do Colo do Útero/virologia
20.
J Food Prot ; 82(4): 669-676, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30917038

RESUMO

HIGHLIGHTS: L. rhamnosus GG in sea buckthorn matrix inhibited E. aerogenes and S. aureus. L. rhamnosus GG was more efficient in sea buckthorn than in apple matrix. Enhanced protection in sea buckthorn matrix may be due to higher phenolic content. WPC and the probiotic increased the pseudoplasticity of the juice matrices.


Assuntos
Enterobacter aerogenes , Lacticaseibacillus rhamnosus , Probióticos , Staphylococcus aureus , Bebidas
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa