Control of wakefulness by lateral hypothalamic glutamatergic neurons in male mice.

The lateral hypothalamus (LH) plays a key role in the maintenance of cortical activation and wakefulness. In the LH, the two main neuronal cell populations consist of excitatory glutamatergic neurons and inhibitory GABAergic neurons. Recent studies have shown that inhibitory LH GABAergic neurons are wake-promoting. However, the mechanism by which excitatory LH glutamatergic neurons contribute to sleep-wake regulation remains unclear. Using fiber photometry in male mice, we demonstrated that LH glutamatergic neurons exhibited high activities during both wakefulness and rapid eye movement sleep. Chemogenetic activation of LH glutamatergic neurons induced an increase in wakefulness that lasted for 6 hr, whereas suppression of LH glutamatergic neuronal activity caused a reduction in wakefulness. Brief optogenetic activation of LH glutamatergic neurons induced an immediate transition from slow-wave sleep to wakefulness, and long-lasting optogenetic stimulation of these neurons maintained wakefulness. Moreover, we found that LH-locus coeruleus/parabrachial nucleus and LH-basal forebrain projections mediated the wake-promoting effects of LH glutamatergic neurons. Taken together, our data indicate that LH glutamatergic neurons are essential for the induction and maintenance of wakefulness. The results presented here may advance our understanding of the role of LH in the control of wakefulness.

Ethanol inhibits histaminergic neurons in mouse tuberomammillary nucleus slices via potentiating GABAergic transmission onto the neurons at both pre- and postsynaptic sites.

AIM: Ethanol, one of the most frequently used and abused substances in our society, has a profound impact on sedation. However, the neuronal mechanisms underlying its sedative effect remain unclear. In this study, we investigated the effects of ethanol on histaminergic neurons in the tuberomammillary nucleus (TMN), a brain region thought to be critical for wakefulness. METHODS: Coronal brain slices (250 µm thick) containing the TMN were prepared from GAD67-GFP knock-in mice. GAD67-GFP was used to identify histaminergic neurons in the TMN. The spontaneous firing and membrane potential of histaminergic neurons, and GABAergic transmission onto these neurons were recorded using whole-cell patch-clamp recordings. Drugs were applied through superfusion. RESULTS: Histaminergic and GAD67-expressing neurons in the TMN of GAD67-GFP mice were highly co-localized. TMN GFP-positive neurons exhibited a regular spontaneous discharge at a rate of 2-4 Hz without burst firing. Brief superfusion of ethanol (64, 190, and 560 mmol/L) dose-dependently and reversibly suppressed the spontaneous firing of the neurons in the TMN; when synaptic transmission was blocked by tetrodotoxin (1 µmol/L), ethanol caused hyperpolarization of the membrane potential. Furthermore, superfusion of ethanol markedly increased the frequency and amplitude of spontaneous and miniature inhibitory postsynaptic currents (sIPSCs and mIPSCs), which were abolished in the presence of the GABAA receptor antagonist bicuculline (20 µmol/L). Finally, ethanol-mediated enhancement of sIPSCs and mIPSCs was significantly attenuated when the slices were pretreated with the GABAB agonist baclofen (30 µmol/L). CONCLUSION: Ethanol inhibits the excitability of histaminergic neurons in mouse TMN slices, possibly via potentiating GABAergic transmission onto the neurons at both pre- and postsynaptic sites.

[Advances in the study of the effect of basal forebrain on sleep-wake regulation].

The basal forebrain(BF) is known to participate in the control of motion, attention, learning and memory, and it also plays a key role in sleep-wake regulation. Although there is a strong heterogeneity among neurons in the BF, the main types are cholinergic, gamma-aminobutyric acid (GABAergic) and glutamatergic neurons. This review provided the research progress in the regulation of sleep-wakefulness behavior by the 3 neurons in the BF. The cholinergic neurons play roles in activation of cortex and promote phase transition between sleep and wakefulness. The cortical projecting GABAergic neurons, which accept the projections from the adjacent cholinergic and glutamatergic neurons, contribute to awakening and the maintenance of normal wakefulness. The GABAergic interneurons may promote sleepiness by inhibiting the wake-active neurons which excite the cortical neurons. The glutamatergic neurons regulate sleep and wakefulness by interacting with neighbor cholinergic and cortical projecting GABAergic neurons or through the direct projection to the cortex as well.

Inhibition of USP1 reverses the chemotherapy resistance through destabilization of MAX in the relapsed/refractory B-cell lymphoma.

The patients with relapsed and refractory diffuse large B-cell lymphoma (DLBCL) have poor prognosis, and a novel and effective therapeutic strategy for these patients is urgently needed. Although ubiquitin-specific protease 1 (USP1) plays a key role in cancer, the carcinogenic effect of USP1 in B-cell lymphoma remains elusive. Here we found that USP1 is highly expressed in DLBCL patients, and high expression of USP1 predicts poor prognosis. Knocking down USP1 or a specific inhibitor of USP1, pimozide, induced cell growth inhibition, cell cycle arrest and autophagy in DLBCL cells. Targeting USP1 by shRNA or pimozide significantly reduced tumor burden of a mouse model established with engraftment of rituximab/chemotherapy resistant DLBCL cells. Pimozide significantly retarded the growth of lymphoma in a DLBCL patient-derived xenograft (PDX) model. USP1 directly interacted with MAX, a MYC binding protein, and maintained the stability of MAX through deubiquitination, which promoted the transcription of MYC target genes. Moreover, pimozide showed a synergetic effect with etoposide, a chemotherapy drug, in cell and mouse models of rituximab/chemotherapy resistant DLBCL. Our study highlights the critical role of USP1 in the rituximab/chemotherapy resistance of DLBCL through deubiquitylating MAX, and provides a novel therapeutic strategy for rituximab/chemotherapy resistant DLBCL.

Ablation of olfactory bulb glutamatergic neurons induces depressive-like behaviors and sleep disturbances in mice.

RATIONALE: Major depression is a serious, but common, psychological disorder, which consists of a long-lasting depressive mood, feelings of helplessness, anhedonia, and sleep disturbances. It has been reported that rats with bilateral olfactory bulbectomies (OBXs) exhibit depressive-like behaviors which indicates that the olfactory bulb (OB) plays an important role in the formation of depression. However, which type of OB neurons plays an important role in the formation of depression remains unclear. OBJECTIVE: To determine the role of OB neuronal types in depression and related sleep-wake dysfunction. METHODS: Firstly, we established and evaluated a conventional physical bilateral OBX depression model. Secondly, we used chemical methods to ablate OB neurons, while maintaining the original shape, and evaluated depressive-like behaviors. Thirdly, we utilized AAV-flex-taCasp3-TEVp and transgenetic mice to specifically ablate the OB GABAergic or glutamatergic neurons, then evaluated depressive-like behaviors. RESULTS: Compared with measured parameters in sham mice, mice with OBXs or ibotenic acid-induced OB lesions exhibited depressive-like behaviors and sleep disturbances, as demonstrated by results of depressive-like behavior tests and sleep recordings. Selective lesioning of OB glutamatergic neurons, but not GABAergic neurons induced depressive-like behaviors and increased rapid eye movement sleep during the light phase of the circadian cycle. CONCLUSIONS: These results indicate that OB glutamatergic neurons play a key role in olfactory-related depression and sleep disturbance.

A retrospective analysis of real-world outcomes of elderly Chinese patients with diffuse large B-cell lymphoma.

BACKGROUND: Elderly patients with diffuse large B-cell lymphoma (DLBCL) have a worse prognosis than younger patients, and the optimal treatment strategy for this group remains controversial. We conducted a retrospective analysis to investigate the clinical features and outcomes of elderly patients (>60 years) and to assess the impact of clinical and molecular factors on outcome in this age group. METHODS: From April 2006 to December 2012, a total of 349 elderly patients with DLBCL from the National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences, and Peking Union Medical College were included in this analysis. Patients were further divided into two age groups (61-69 years and ≥70 years). We compared clinical characteristics and outcomes between groups. RESULTS: Of 349 total patients, 204 (58.5%) were aged 61 to 69 years, and 145 (41.5%) patients were aged 70 years or older. Except for the Eastern Cooperative Oncology Group performance status, clinical characteristics were comparable between the two groups. With a median follow-up of 82 (range, 1-129) months, the 5-year overall survival (OS) and progression-free survival (PFS) rates were 51.9% and 45.8%, respectively. The 5-year OS rates for patients aged 61 to 69 years and those over 70 years were 58.3% and 42.8% (P = 0.007), respectively, and the 5-year PFS rates were 51.0% and 38.6% (P = 0.034). Treatment regimens including rituximab provided a higher 5-year OS rate (63.1% vs. 37.1%, P < 0.001) and PFS rate (56.6% vs. 31.8%, P < 0.001) than chemotherapy alone. For patients aged 61 to 69 years, chemotherapy plus rituximab resulted in a higher 5-year OS rate (66.7% vs. 46.4%, P = 0.002) and PFS rate (60.0% vs. 38.1%, P = 0.002) than chemotherapy alone. For patients aged ≥70 years, there was a marked survival advantage in patients who received chemotherapy plus rituximab (5-year OS rate: 57.7% vs. 25.4%, P < 0.001; 5-year PFS rate: 51.3% vs. 23.9%, P < 0.001) compared with that seen in those who received chemotherapy alone. Multivariate analysis established that stage III/IV disease, elevated lactate dehydrogenase (LDH), initial treatment, and chemotherapy with rituximab were independent risk factors for 5-year OS, and stage III/IV disease, elevated LDH, and chemotherapy with rituximab were independent risk factors for 5-year PFS for elderly patients with DLBCL. CONCLUSIONS: In comparison to patients aged 61 to 69 years, those aged ≥70 years have poorer survival. Prolonged survival is obtainable with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP)-like in elderly Chinese patients in all age groups, indicating that the R-CHOP-like regimen should be considered for this population, even for those aged 70 years or older.

iRNAm5C-PseDNC: identifying RNA 5-methylcytosine sites by incorporating physical-chemical properties into pseudo dinucleotide composition.

Occurring at cytosine (C) of RNA, 5-methylcytosine (m5C) is an important post-transcriptional modification (PTCM). The modification plays significant roles in biological processes by regulating RNA metabolism in both eukaryotes and prokaryotes. It may also, however, cause cancers and other major diseases. Given an uncharacterized RNA sequence that contains many C residues, can we identify which one of them can be of m5C modification, and which one cannot? It is no doubt a crucial problem, particularly with the explosive growth of RNA sequences in the postgenomic age. Unfortunately, so far no user-friendly web-server whatsoever has been developed to address such a problem. To meet the increasingly high demand from most experimental scientists working in the area of drug development, we have developed a new predictor called iRNAm5C-PseDNC by incorporating ten types of physical-chemical properties into pseudo dinucleotide composition via the auto/cross-covariance approach. Rigorous jackknife tests show that its anticipated accuracy is quite high. For most experimental scientists' convenience, a user-friendly web-server for the predictor has been provided at http://www.jci-bioinfo.cn/iRNAm5C-PseDNC along with a step-by-step user guide, by which users can easily obtain their desired results without the need to go through the complicated mathematical equations involved. It has not escaped our notice that the approach presented here can also be used to deal with many other problems in genome analysis.

iRNA-2methyl: Identify RNA 2'-O-methylation Sites by Incorporating Sequence-Coupled Effects into General PseKNC and Ensemble Classifier.

OBJECTIVE: Being a kind of post-transcriptional modification (PTCM) in RNA, the 2'-Omethylation modification occurs in the processes of life development and disease formation as well. Accordingly, from the angles of both basic research and drug development, we are facing a challenging problem: given an uncharacterized RNA sequence formed by many nucleotides of A (adenine), C (cytosine), G (guanine), and U (uracil), which one can be of 2-O'-methylation modification, and which one cannot? Unfortunately, so far no computational method whatsoever has been developed to address such a problem. METHOD: To fill this empty area, we propose a predictor called iRNA-2methyl. It is formed by incorporating a series of sequence-coupled factors into the general PseKNC (pseudo nucleotide composition), followed by fusing 12 basic random forest classifier into four ensemble predictors, with each aimed to identify the cases of A, C, G, and U along the RNA sequence concerned, respectively. RESULTS: Rigorous jackknife cross-validations have indicated that the success rates are very high (>93%). For the convenience of most experimental scientists, a user-friendly web-server for iRNA-2methyl has been established at http://www.jci-bioinfo.cn/iRNA-2methyl, by which users can easily obtain their desired results without the need to go through the complicated mathematical equations involved. CONCLUSION: The proposed predictor iRNA-2methyl will become a very useful bioinformatics tool for medicinal chemistry, helping to design effective drugs against the diseases related to the 2'-Omethylation modification.

Small-Cell Lung Cancer Transformation in Patients With Pulmonary Adenocarcinoma: A Case Report and Review of Literature.

Despite the demonstrated benefit from epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor (TKI) based therapies, EGFR mutant lung adenocarcinoma will eventually acquire drug resistance. Transformation to small-cell lung cancer (SCLC) is considered to be a rare resistance mechanism of EGFR-TKI therapy.We describe a case of a 46-year-old man presenting with refractory cough. Percutaneous transthoracic biopsy was performed and confirmed an EGFR exon 21 L858R lung adenocarcinoma. However, the patient relapsed after successful treatment with gefitinib for 1 year, at which point rebiopsy identified an SCLC and chemotherapy composed of platinum and pemetrexed was started. However, despite the brief success of chemotherapy, our patient died of aggressive cancer progression and complications of chemotherapy.Our case highlights the importance of rebiopsy when managing drug resistance and presents a possible origin of the transformed cells. We also summarize the clinical characteristics of cases involving transformed SCLC from previous studies and discuss whether it could be a new subtype of SCLC.