RESUMO
BACKGROUND: Accumulating evidence shows that tumor cell-specific genomic changes can influence the cross talk between cancer cells and the surrounding tumor microenvironment (TME). Loss of the PTEN tumor suppressor gene is observed in 20% to 30% of prostate cancers (PCa) when first detected and the rate increases with PCa progression and advanced disease. Recent findings implicate a role for PTEN in cellular type I interferon response and immunosuppression in PCa. However, the way that PTEN inactivation alters antitumor immune response in PCa is poorly understood. MATERIALS AND METHODS: To investigate the changes associated with PTEN loss and an immunosuppressive TME in PCa, we used CIBERSORT to estimate the relative abundance of 22 immune-cell types from 741 primary and 96 metastatic tumors. Our in silico findings were then validated by immunohistochemical analysis of immune cells and IDO1 and PDL1 checkpoint proteins in a cohort of 94 radical prostatectomy specimens. RESULTS: FoxP3+ T regulatory cells (Tregs) were significantly increased in PTEN-deficient PCa in all three public domain cohorts. Loss of PTEN in bone metastases was associated with lower CD8+ T-cell abundance, but in liver metastasis, FoxP3+ Tregs were present at higher levels. PTEN-deficient lymph node metastasis had a distinct profile, with high levels of CD8+ T cells. Moreover, we found that metastatic PCa presents higher abundance of FoxP3+ Treg when compared to primary lesions. Since PTEN-deficient tumors are likely to be immunosuppressed as a consequence of increased FoxP3+ Tregs, we then evaluated the localization and expression of IDO1, PDL1 immune checkpoints, and the corresponding density of FoxP3+ Treg and CD8+ T cells using our validation cohort (n = 94). We found that IDO1 protein expression and FoxP3+ Treg density were higher in neoplastic glands compared with benign adjacent tissue. Moreover, higher densities of FoxP3+ Treg cells in both stromal (P = 0.04) and tumor (P = 0.006) compartments were observed in PTEN-deficient tumors compared to tumors that retained PTEN activity. Similarly, IDO1 protein expression was significantly increased in the tumor glands of PTEN-deficient PCa (P < 0.0001). Spearman correlation analysis showed that IDO1 expression was significantly associated with FoxP3+ Treg and CD8+ T-cell density (P < 0.01). CONCLUSIONS: Our findings imply that PTEN deficiency is linked to an immunosuppressive state in PCa with distinct changes in the frequency of immune cell types in tumors from different metastatic sites. Our data suggest that determining PTEN status may also help guide the selection of patients for future immunotherapy trials in localized and metastatic PCa.
Assuntos
Fatores de Transcrição Forkhead/imunologia , Indolamina-Pirrol 2,3,-Dioxigenase/imunologia , Linfócitos do Interstício Tumoral/imunologia , PTEN Fosfo-Hidrolase/deficiência , Neoplasias de Próstata Resistentes à Castração/imunologia , Linfócitos T Reguladores/imunologia , Idoso , Antígeno B7-H1/imunologia , Estudos de Coortes , Fatores de Transcrição Forkhead/biossíntese , Humanos , Tolerância Imunológica , Indolamina-Pirrol 2,3,-Dioxigenase/biossíntese , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , PTEN Fosfo-Hidrolase/genética , PTEN Fosfo-Hidrolase/imunologia , Neoplasias de Próstata Resistentes à Castração/enzimologia , Neoplasias de Próstata Resistentes à Castração/genética , Análise Serial de Tecidos , Microambiente Tumoral/imunologiaRESUMO
Phosphatase and tensin homolog (PTEN) is an important protein with key modulatory functions in cell growth and survival. PTEN is crucial during embryogenesis and plays a key role in the central nervous system (CNS), where it directly modulates neuronal development and synaptic plasticity. Loss of PTEN signaling function is associated with cognitive deficits and synaptic plasticity impairment. Accordingly, Pten mutations have a strong link with autism spectrum disorder. In this study, neuronal Pten haploinsufficient male mice were subjected to a long-term environmental intervention - intermittent fasting (IF) - and then evaluated for alterations in exploratory, anxiety and learning and memory behaviors. Although no significant effects on spatial memory were observed, mutant mice showed impaired contextual fear memory in the passive avoidance test - an outcome that was effectively rescued by IF. In this study, we demonstrated that IF modulation, in addition to its rescue of the memory deficit, was also required to uncover behavioral phenotypes otherwise hidden in this neuronal Pten haploinsufficiency model.
Assuntos
Disfunção Cognitiva/terapia , Jejum , Haploinsuficiência , PTEN Fosfo-Hidrolase/deficiência , Animais , Transtornos de Ansiedade/terapia , Comportamento Animal , Deficiências da Aprendizagem/terapia , Masculino , Transtornos da Memória/terapia , CamundongosRESUMO
Deletion of the mTOR pathway inhibitor PTEN from postnatally-generated hippocampal dentate granule cells causes epilepsy. Here, we conducted field potential, whole cell recording and single cell morphology studies to begin to elucidate the mechanisms by which granule cell-specific PTEN-loss produces disease. Cells from both male and female mice were recorded to identify sex-specific effects. PTEN knockout granule cells showed altered intrinsic excitability, evident as a tendency to fire in bursts. PTEN knockout granule cells also exhibited increased frequency of spontaneous excitatory synaptic currents (sEPSCs) and decreased frequency of inhibitory currents (sIPSCs), further indicative of a shift towards hyperexcitability. Morphological studies of PTEN knockout granule cells revealed larger dendritic trees, more dendritic branches and an impairment of dendrite self-avoidance. Finally, cells from both female control and female knockout mice received more sEPSCs and more sIPSCs than corresponding male cells. Despite the difference, the net effect produced statistically equivalent EPSC/IPSC ratios. Consistent with this latter observation, extracellularly evoked responses in hippocampal slices were similar between male and female knockouts. Both groups of knockouts were abnormal relative to controls. Together, these studies reveal a host of physiological and morphological changes among PTEN knockout cells likely to underlie epileptogenic activity. SIGNIFICANCE STATEMENT: Hyperactivation of the mTOR pathway is associated with numerous neurological diseases, including autism and epilepsy. Here, we demonstrate that deletion of the mTOR negative regulator, PTEN, from a subset of hippocampal dentate granule impairs dendritic patterning, increases excitatory input and decreases inhibitory input. We further demonstrate that while granule cells from female mice receive more excitatory and inhibitory input than males, PTEN deletion produces mostly similar changes in both sexes. Together, these studies provide new insights into how the relatively small number (≈200,000) of PTEN knockout granule cells instigates the development of the profound epilepsy syndrome evident in both male and female animals in this model.
Assuntos
Hipocampo/metabolismo , Hipocampo/patologia , Neurônios/metabolismo , Neurônios/patologia , PTEN Fosfo-Hidrolase/deficiência , Caracteres Sexuais , Animais , Contagem de Células , Epilepsia/metabolismo , Epilepsia/patologia , Feminino , Imuno-Histoquímica , Masculino , Potenciais da Membrana/fisiologia , Camundongos Knockout , Microscopia Confocal , Inibição Neural/fisiologia , PTEN Fosfo-Hidrolase/genética , Técnicas de Patch-Clamp , Técnicas de Cultura de TecidosRESUMO
Mucocutaneous papillomas can be manifestations of an autosomal dominant condition known as Cowden syndrome (CS). We report the case of a 22-year-old man with oral and cutaneous papules and a past history of thyroid malignancy. It is important to recognize oral manifestations of CS; they can lead to early diagnosis of the condition.