Longitudinal dynamic single-cell mass cytometry analysis of peripheral blood mononuclear cells in COVID-19 patients within 6 months after viral RNA clearance.

This study investigates the longitudinal dynamic changes in immune cells in COVID-19 patients over an extended period after recovery, as well as the interplay between immune cells and antibodies. Leveraging single-cell mass spectrometry, we selected six COVID-19 patients and four healthy controls, dissecting the evolving landscape within six months post-viral RNA clearance, alongside the levels of anti-spike protein antibodies. The T cell immunophenotype ascertained via single-cell mass spectrometry underwent validation through flow cytometry in 37 samples. Our findings illuminate that CD8 + T cells, gamma-delta (gd) T cells, and NK cells witnessed an increase, in contrast to the reduction observed in monocytes, B cells, and double-negative T (DNT) cells over time. The proportion of monocytes remained significantly elevated in COVID-19 patients compared to controls even after six-month. Subpopulation-wise, an upsurge manifested within various T effector memory subsets, CD45RA + T effector memory, gdT, and NK cells, whereas declines marked the populations of DNT, naive and memory B cells, and classical as well as non-classical monocytes. Noteworthy associations surfaced between DNT, gdT, CD4 + T, NK cells, and the anti-S antibody titer. This study reveals the changes in peripheral blood mononuclear cells of COVID-19 patients within 6 months after viral RNA clearance and sheds light on the interactions between immune cells and antibodies. The findings from this research contribute to a better understanding of immune transformations during the recovery from COVID-19 and offer guidance for protective measures against reinfection in the context of viral variants.

Cellular Senescence in Acute Liver Injury: What Happens to the Young Liver?

Cellular senescence, characterized by irreversible cell cycle arrest, not only exists in age-related physiological states, but has been found to exist in various diseases. It plays a crucial role in both physiological and pathological processes and has become a trending topic in global research in recent years. Acute liver injury (ALI) has a high incidence worldwide, and recent studies have shown that hepatic senescence can be induced following ALI. Therefore, we reviewed the significance of cellular senescence in ALI. To minimize the potential confounding effects of aging on cellular senescence and ALI outcomes, we selected studies involving young individuals to identify the characteristics of senescent cells, the value of cellular senescence in liver repair, its regulation mechanisms in ALI, its potential as a biomarker for ALI, the prospect of treatment, and future research directions.

A novel exoskeletal-derived C-type lectin facilitates phagocytosis of hemocytes in the oriental river prawn Macrobrachium nipponense.

C-type lectins (CTLs) execute critical functions in multiple immune responses of crustaceans as a member of pattern recognition receptors (PRRs) family. In this study, a novel CTL was identified from the exoskeleton of the oriental river prawn Macrobrachium nipponense (MnLec3). The full-length cDNA of MnLec3 was 1150 bp with an open reading frame of 723 bp, encoding 240 amino acids. MnLec3 protein contained a signal peptide and one single carbohydrate-recognition domain (CRD). MnLec3 transcripts were widely distributed at the exoskeleton all over the body. Significant up-regulation of MnLec3 in exoskeleton after Aeromonas hydrophila challenged suggested the involvement of MnLec3 as well as the possible function of the exoskeleton in immune response. In vitro tests with recombinant MnLec3 protein (rMnLec3) manifested that it had polysaccharide binding activity, a wide spectrum of bacterial binding activity and agglutination activity only for tested Gram-negative bacteria (Escherichia coli, Vibrio anguillarum and A. hydrophila). Moreover, rMnLec3 significantly promoted phagocytic ability of hemocytes against A. hydrophila in vivo. What's more, MnLec3 interference remarkably impaired the survivability of the prawns when infected with A. hydrophila. Collectively, these results ascertained that MnLec3 derived from exoskeleton took an essential part in immune defense of the prawns against invading bacteria as a PRR.

The 90-Day Survival Threshold: A Pivotal Determinant of Long-Term Prognosis in HBV-ACLF Patients - Insights from a Prospective Longitudinal Cohort Study.

This work aims to explore the long-term prognosis of hepatitis B virus-related acute-on-chronic liver failure (HBV-ACLF). In this prospective study, eligible inpatients with HBV-ACLF are enrolled and followed up from December 2012 to February 2023, for clinical events, laboratory tests at least every 6 months. Overall, the survival rates at 28 days, 90 days, 1 year, 5 years, and 8 years are 64.7%, 48.8%, 46.1%, 43.8%, and 42.2%, respectively. Among the 8-year mortality and liver transplant cases, ACLF survivors (who survived over 90 days) accounted for 7.8% (9/115). Among 101 patients who survived for more than 90 days, 97.9% of patients achieve virologic response at 1 year. For HBeAg-positive patients, the HBeAg seroconversion are 25.5%, 63.6%, and 76.9% at 1, 5, and 8 years, respectively. Alanine aminotransferase, aspartate aminotransferase, total bilirubin, INR, white blood cell count, and albumin levels gradually improve within the first year. Fibrosis biomarkers APRI, FIB-4 and Chitinase-3-like protein 1 (CHI3L1) levels decreases within the first 5 years. The Cox proportional hazards regression reveal that high total bilirubin (HR = 1.008, p = 0.021) is the independent risk factor for 8-year survival of ALCF survivors. The 90-day period following of HBV-ACLF represented a critical juncture for long-term prognosis, revealing favorable outcomes beyond this timeframe.

Lower rate of mpox vaccination hesitancy and medical consultation among Chinese men who have sex with men living with HIV in comparison with those living without HIV: A national observational study.

This anonymous cross-sectional study aimed to investigate the relationships between HIV infection and mpox-related focus issues among Chinese men who have sex with men (MSM). This study involved in 27 MSM social organizations and was conducted from July 31 to August 4, 2023. Mpox vaccination hesitancy was defined as the proportion of participants who expressed unwillingness to receive self-funded and free vaccines. Logistic regression models were employed to estimate odds ratios (OR) and 95% confidence interval (95%CI). Of 7196 MSMs, the prevalence of mpox differed between people living with HIV (PLWH) (1.04%, 20/1920) and people living without HIV (PLWoH) (0.55%, 29/5276) (P = .037). However, after adjusting for all covariates, there was no significant association between HIV status and mpox (aOR = 1.17; 95%CI = 0.58, 2.39; P = .658). Furthermore, the crude rates of vaccination hesitation (PLWoH: 5.91%, PLWH: 4.11%; P = .004) and consultation hesitation (PLWoH: 16.22%, PLWH: 10.78%; P < .001) were both lower in the PLWH. Compared with PLWoH, PLWH had lower odds ratios of vaccination hesitation (aOR = 0.70; 95%CI = 0.53, 0.92; P = .011) and consultation hesitation (aOR = 0.74; 95%CI = 0.60, 0.90; P = .003) among MSM. The estimate of association between HIV status and consultation hesitation was even smaller among MSM who reported hepatitis C infection or uncertainty (aOR = 0.30; 95%CI = 0.15, 0.56), compared with those without hepatitis C (aOR = 0.73; 95%CI = 0.60, 0.89) (P for interaction = .037). MSM living with HIV in China demonstrated a greater willingness to accept mpox vaccination and medical consultation. In the future, it is recommended that medical institutions establish good medical environment to control the mpox epidemic, especially for PLWH.

The prevalence of mpox and its association with sexual behavior among Chinese men who have sex with men in early August 2023.

Study investigating mpox infection and its association with sexual behavior among men who have sex with men (MSM) in China was lacking. This observational survey aimed to provide evidence on detail characteristics of mpox cases and sexual behavior, then analyze their relationship among MSM in China to help formulate prevention and control policies. An anonymous cross-sectional study was conducted in 27 MSM social organizations across 21 provinces, municipalities, and autonomous regions from July 31 to August 4, 2023. A safe sexual behavior index was constructed based on three risky sexual behaviors in the last month, including condomless anal intercourse, commercial sex and group sex. High safe sexual behavior indicated that the participant engaged in none of the three, and low safe sexual behavior indicated that they engaged in all three behaviors; otherwise, moderate safe sexual behavior was indicated. Among 7538 MSM, the prevalence of mpox was 0.73% (55/7538). The proportion of high safe sexual behavior was 79.64% (6003/7538). The crude prevalence of mpox was lower in the high safe sexual behavior group (0.35%, 21/6003), compared with the low (12.12%, 8/66) and moderate safe (1.78%, 26/1469) sexual behavior group. In the multivariable-adjusted analysis, after adjusting for all covariates, compared with low safe sexual behavior group, moderate safe sexual behavior group (aOR = 0.21; 95% CI = 0.08, 0.54) and high safe sexual behavior group (aOR = 0.04; 95% CI = 0.02, 0.12) both had lower risk of mpox. Of three sexual behaviors, MSM who reported no commercial sex had the lowest risk of mpox (aOR = 0.23; 95% CI = 0.13, 0.41), compared with those who reported commercial sex in the last month. The other two safe sexual behaviors both were associated with lower risk of mpox (no group sex vs. group sex: aOR = 0.15; 95% CI = 0.08, 0.28; no condomless anal intercourse vs. condomless anal intercourse: aOR = 0.23; 95% CI = 0.13, 0.41). The prevalence of mpox virus infection was nearly 1% among MSM in China. Strengthening mpox surveillance, emphasizing safe sexual behavior in health education are essential for the control of mpox among MSM in China.

Mpox Vaccination Hesitancy and Its Associated Factors among Men Who Have Sex with Men in China: A National Observational Study.

More than 400 confirmed mpox cases have been reported in China. The mpox vaccination is crucial to mitigate mpox transmission, especially for at-risk populations. This study aimed to determine mpox vaccination hesitancy and its associated factors in Chinese men who have sex with men (MSM). This nationwide cross-sectional study was conducted among 7538 Chinese MSM in 27 MSM social organizations from 21 provinces, municipalities, and autonomous regions of China from 31 July to 4 August 2023. Of them, the rate of mpox vaccination hesitancy was 5.59% (421/7538). The most common reason for mpox vaccination hesitation was concerns of safety and side effects (62.71%, 264/421), followed by concerns of privacy (38.24%, 161/421), thoughts of impossible infection (37.53%, 158/421), no effectiveness in preventing reinfection (30.88%, 130/421), and no worry about infection (12.35%, 52/421). Regarding the concerning characteristics of the vaccines, concerns of vaccine safety ranked first (71.74%, 5408/7538), followed by vaccine effectiveness (14.05%, 1059/7538), vaccine costs (7.35%, 554/7538), and the continuity of vaccine effectiveness (3.91%, 295/7538). The highest odds ratio of mpox vaccination hesitation was seen in MSM who were infected with mpox virus (aOR = 2.38; 95%CI = 1.08, 5.23), followed by those aged ≥60 years (aOR = 2.25; 95%CI = 1.31, 3.88), those who were unemployed (aOR = 1.66; 95%CI = 1.25, 2.19), and those who had an education level of postgraduate and above (aOR = 1.55; 95%CI = 1.01, 2.37). However, MSM who had a higher level of mpox-related knowledge (moderate: aOR = 0.53; 95%CI = 0.36, 0.77; high: aOR = 0.30; 95%CI = 0.23, 0.40) had a lower odds ratio of mpox vaccination hesitation. MSM in China had low hesitancy toward mpox vaccination. The safety and effectiveness of the vaccine and privacy were important aspects of hesitancy. Health education on mpox-related knowledge should be encouraged to promote future vaccination plans.

The outcome of ibrutinib-based regimens in relapsed/refractory central nervous system lymphoma and the potential impact of genomic variants.

BACKGROUND: Relapsed/refractory (r/r) central nervous system lymphoma (CNSL) exhibits aggressive behavior and poor outcomes. As an effective bruton tyrosine kinase (BTK) inhibitor, ibrutinib yields benefits in B-cell malignancies. OBJECTIVES: We aimed to explore the efficacy of ibrutinib in treating r/r CNSL patients, and whether genomic variants impact treatment outcomes. MATERIAL AND METHODS: The ibrutinib-based regimens in 12 r/r primary CNSL (PCNSL) and 2 secondary CNSL (SCNSL) patients were analyzed retrospectively. The impact of genetic variants on the effects of treatments was examined using whole-exome sequencing (WES) technology. RESULTS: In PCNSL, the overall response rate was 75%, with median overall survival (OS) not reached (NR) and progression-free survival (PFS) of 4 months. Both SCNSL patients responded to ibrutinib, with median OS NR and PFS of 0.5-1.5 months. Infections were common during ibrutinib therapy (42.86%). The PCNSL patients harboring gene mutations in PIM1, MYD88 and CD79B, and the proximal BCR and nuclear factor kappa B (NF-κB) pathways responded to ibrutinib. Patients who harbored simple genetic variants and those with a low tumor mutation burden (TMB; 2.39-5.56/Mb) responded swiftly and maintained remission for more than 10 months. A patient with a TMB of 11/Mb responded to ibrutinib but continued to experience disease progression. In contrast, patients with complex genomic features, especially extremely high TMB (58.39/Mb), responded poorly to ibrutinib. CONCLUSIONS: Our study demonstrates that ibrutinib-based therapy is effective and relatively safe for the treatment of r/r CNSL. Patients with less genomic complexity, especially with regard to TMB, might benefit more from ibrutinib regimens.

Awareness of mpox-related knowledge among men who have sex with men in China.

BACKGROUND: With the rapid spread of the mpox epidemic, cases have emerged in multiple countries, mainly among men who have sex with men. Because of the connectedness of today's world, countries have to be prepared to face risks in advance. Therefore, this study aimed to investigate awareness of mpox-related knowledge among men who have sex with men in China. METHODS: With the assistance of the social organizations of men who have sex with men, a cross-sectional survey of men who have sex with men in China was conducted through an online questionnaire between July 1 and July 18, 2022. A nationwide sample of Chinese men who have sex with men (N = 3,257) was recruited. RESULTS: Only 36.9% of participants had mpox-related knowledge. Awareness of mpox-related knowledge among respondents was positively associated with those in older age groups (33 to 42 years and 51 years or older) (adjusted odds ratio [AOR] = 1.31; 95% confidence interval [CI]: 1.03-1.67, AOR = 1.61; 95% CI: 1.16-2.24; respectively), married (AOR = 1.55; 95% CI: 1.09-2.19), and those with a graduate degree or above (AOR = 2.14; 95% CI: 1.11-4.13), while negatively associated with those living in the western parts of China (AOR = 0.74; 95% CI: 0.60-0.92), and those who were unsure of their history of Human Immunodeficiency Virus (HIV) status (AOR = 0.44; 95% CI: 0.30-0.63). CONCLUSION: Mpox-related knowledge is fairly low among men who have sex with men in China. China needs to spread knowledge to the public through multiple channels, especially in key populations (men who have sex with men, HIV-infected, etc.), and take preventive measures to effectively avoid outbreaks of mpox.

Girdin acts as an oncogene in gastric cancer by regulating AKT/GSK3ß/ß-catenin signaling.

ThE present work focused on exploring Girdin expression within gastric cancer (GC), examining the effect of Girdin on the cell phenotype of GC, and clarifying the underlying mechanisms. Girdin expression in GC samples was identified by immunohistochemistry (IHC) and quantitative real-time PCR (qRT-PCR) assays. Girdin-targeting siRNAs were transfected into GC cells; later, we examined GC cell proliferation, migration, invasion, and apoptosis, respectively. Additionally, the protein expression was examined through Western blotting assay. Moreover, the tumor implantation experiment was conducted for examining Girdin knockdown in vivo. The results showed that Girdin expression elevated within GC samples, which was associated with the dismal prognostic outcome. Girdin knockdown suppressed GC cell proliferation, migration, and invasion, and enhanced apoptosis and cell cycle arrest. Girdin promoted the phosphorylation of AKT, GSK3ß, and ß-catenin. Moreover, Girdin inhibited the phosphorylation of ß-catenin. Girdin suppressed cell apoptosis and stimulated cell migration and invasion, while AKT inhibitor (MK2206) treatment reversed the effect of Girdin overexpression, and GSK3ß inhibitor (CHIR99021) treatment enhanced the effect of Girdin overexpression on GC cells. Besides, Girdin delayed tumor growth in vivo. In conclusion, Girdin was abnormally expressed in GC samples, which promoted the development of GC by regulating AKT/GSK3ß/ß-catenin signaling.

Knowledge and vaccination acceptance toward the human monkeypox among men who have sex with men in China.

Background: MSM individuals are at high risk of monkeypox infection, and judicious use of vaccines can control the outbreak. Therefore, we conducted a national cross-sectional survey to assess the vaccination willingness, associated factors, and related knowledges of monkeypox among MSM individuals in China. Methods: This anonymous cross-sectional study was conducted in China from July 1 to July 3, 2022, and electronic questionnaires were sent online to MSM individuals of specific institutions. Men, aged 18 or older, who had anal sex in the past year were recruited. Multivariable logistic regression models and univariable logistic regression models were performed in different groups of participants, including all eligible respondents, people with or without self-reported HIV infection, and people who had sex with at least one male sexual partner in last month. Results: A total of 2,618 male respondents, including 2,134 homosexuals and 484 bisexuals, were enrolled in our final analysis. Most of the respondents had a certain understanding of the source of infection, transmission route, and preventive measures, but lacked knowledge of the susceptible population, clinical manifestations, vaccination, and treatment. In total, 90.2% of all respondents were willing to receive the vaccines against monkeypox. Among people with self-reported HIV infection, the vaccination acceptance rate was 91.7%, while it was 89.7% in the rest. The main influencing factors were knowledge about monkeypox (moderate: aOR = 1.47, 95% CI: 1.04-2.08; high: aOR = 2.03, 95% CI: 1.23-3.34), knowledge about prevention measures (moderate: aOR = 3.52, 95% CI: 2.51-4.94; high: aOR = 5.32, 95% CI: 2.98-9.47), concerns about their susceptibility to monkeypox infection (aOR = 4.37, 95% CI: 3.29-5.80), and possible contact with people and animals in epidemic areas (aOR = 0.42, 95% CI: 0.25-0.70). For self-reported HIV-infected individuals, education (bachelor degree: aOR = 0.40, 95% CI: 0.18-0.89) and poor condom use (sometimes: aOR = 2.18, 95% CI: 1.06-4.47) may also affect the vaccination. Conclusions: There was still a lack of knowledge about the human monkeypox among MSM individuals in China. The vaccination acceptance rate of this high-risk population was high, and it was closely related to the knowledge factors, fear of infection, and possible contact with people or animals in affected areas. Targeted publicity and education of the high-risk groups, vaccination pre-arranged planning should be formulated to cope with the further development of this infectious disease.

Metformin Facilitates Osteoblastic Differentiation and M2 Macrophage Polarization by PI3K/AKT/mTOR Pathway in Human Umbilical Cord Mesenchymal Stem Cells.

Mesenchymal stem cells (MSCs) are the most promising multipotent stem cells that can differentiate into osteoblasts, chondrocytes, and adipocytes. This cellular flexibility contributes to widespread clinical use of MSCs in tissue repair and regeneration. The immune system is a key player in regulating bone remodeling. In recent years, the association between the immune system and bone metabolism has become an increasing focus of interest. Metformin, a glucose-lowering drug, exerts powerful impact on metabolic signaling. However, whether metformin can modulate bone metabolism or whether metformin can influence immune milieu by regulation of macrophages has not been thoroughly elucidated. Herein, we specifically explored the complex interactions between macrophages and human umbilical cord mesenchymal stem cells (UC-MSCs) in the context of metformin. Our research demonstrated that metformin not only stimulated osteogenesis of UC-MSCs but also influenced the immune system via promoting M2 but reducing M1 macrophages. Mechanically, we found that metformin-treated M2 macrophages possessed more potent osteoinductive capacity in our coculture system. Molecularly, these metformin-stimulated M2 macrophages facilitated osteogenesis via activating the PI3K/AKT/mTOR pathway. As demonstrated by using PI3K-specific inhibitor LY294002, we found that the pathway inhibitor partly reversed osteoinductive activity which was activated by coculture of metformin-treated M2 macrophages. Overall, our novel research illuminated the cooperative and synergistic effects of metformin and M2 macrophages on the dynamic balance of bone metabolism.

NOL6 Regulates the Proliferation and Apoptosis of Gastric Cancer Cells via Regulating TP53I3, CDK4 and MCM7 Expression.

Background: Gastric cancer (GC) is a prevalent cancer with high mortality and strong invasiveness, and the entire regulatory networks of GC is still unclear. Objective: The aim of this study was to explore the specific mechanism of the effect of nucleolar protein 6 (NOL6) on the proliferation and apoptosis of GC cells. Methods: The human gastric adenocarcinoma cell line HGC-27 and AGS were cultured. qRT-PCR was used to verify the expression level of NOL6 in GC cells; MTT and EdU were used to test cell proliferation; TUNEL staining and Flow cytometry were used to detect cell apoptosis; The downstream genes and pathways following NOL6 knockdown were explored through the microarray assay and ingenuity pathway analysis, and the downstream genes were finally verified by qRT-PCR and Western blotting. The xenograft mice were used to investigate the effect of NOL6 on GC in vivo. Results: TCGA data analysis showed that NOL6 expression level was higher in GC cells than adjacent normal cells. Over-expression of NOL6 increased proliferation and colony formation, and inhibited the apoptotic rate in AGS and HGC-27 cells, while NOL6 knockdown induced the opposite effects. Through microarray assay and IPA analysis, NOL6-related downstream genes and critical signaling pathways were found. And we verified the relationship between downstream genes and GC. Additionally, NOL6 knockdown could decrease the weight and volume of tumor in the mice. Conclusion: NOL6 knockdown could inhibit cell proliferation and induce cell apoptosis of GC, suggesting that NOL6 may serve as a potential therapeutic target for treating GC.

Driver Genes Associated With the Incidence of Venous Thromboembolism in Patients With Non-Small-Cell Lung Cancer: A Systematic Review and Meta-Analysis.

BACKGROUND: The association between driver genes and the incidence of thromboembolic events (TEs) in patients diagnosed with non-small-cell lung cancer (NSCLC) needs to be quantified to guide clinical management. METHODS: We interrogated PubMed, Embase, Web of Science and Cochrane library databases for terms related to venous thromboembolism (VTE) and arterial thromboembolism (ATE) in patients diagnosed with non-small-cell lung cancer harboring driver genes. This search was conducted for studies published between 1 January, 2000 and 31 December, 2020. A random-effects meta-analysis was performed to analyze the pooled incidence and odds ratios of VTE in patients with different driver genes. RESULTS: Of the 2,742 citations identified, a total of 25 studies that included 21,156 patients met eligibility criteria. The overall pooled incidence of VTE in patients with driver genes was 23% (95% CI 18-29). Patients with ROS1 rearrangements had the highest incidence of VTE (37%, 95%CI 23-52). ALK rearrangements were associated with increased VTE risks (OR=2.08,95% CI 1.69-2.55), with the second highest incidence of VTE (27%, 95%CI 20-35). Both groups of patients with EGFR and KRAS mutations did not show a significantly increased risk for VTE (OR=1.33, 95% CI 0.75-2.34; OR=1.31, 95% CI 0.40-4.28). CONCLUSIONS: ALK rearrangements were shown to be associated with increased VTE risks in patients diagnosed with non-small lung cancer, while there was no significant relation observed between VTE risks and EGFR or KRAS mutations in lung cancer patients.

Phospholipase D as a key modulator of cancer progression.

The phospholipase D (PLD) family has a ubiquitous expression in cells. PLD isoforms (PLDs) and their hydrolysate phosphatidic acid (PA) have been demonstrated to engage in multiple stages of cancer progression. Aberrant expression of PLDs, especially PLD1 and PLD2, has been detected in various cancers. Inhibition or elimination of PLDs activity has been shown to reduce tumour growth and metastasis. PLDs and PA also serve as downstream effectors of various cell-surface receptors, to trigger and regulate propagation of intracellular signals in the process of tumourigenesis and metastasis. Here, we discuss recent advances in understanding the functions of PLDs and PA in discrete stages of cancer progression, including cancer cell growth, invasion and migration, and angiogenesis, with special emphasis on the tumour-associated signalling pathways mediated by PLDs and PA and the functional importance of PLDs and PA in cancer therapy.

Sec3 knockdown inhibits TGF-ß induced epithelial-mesenchymal transition through the down-regulation of Akt phosphorylation in A549 cells.

The exocyst, an evolutionarily conserved octomeric protein complex, has been demonstrated as an essential component for vesicle tethering during cell exocytosis, and participates in various physiological processes in the cell. Although subunits of the exocyst complex have been reported to be involved in the regulation of TGF-ß induced cancer cell migration and epithelial-mesenchymal transition (EMT), the potential function of Sec3 in these regulated processes remains unclear. Here, we show that Sec3 knockdown abolishes TGF-ß stimulated A549 lung cancer cell migration in vitro and causes defects in the regulated EMT process. In addition, we find that depletion of Sec3 significantly inhibits TGF-ß stimulated Akt phosphorylation in A549 cells, whereas the increase of Smad2 phosphorylation is unaffected. Furthermore, replenishment of an RNAi-resistant form of Sec3 is shown to restore the defects of TGF-ß induced cell migration, EMT and Akt signaling activation. In summary, our study provides evidence that Sec3 is involved in TGF-ß induced cell migration and EMT processes, presumably through the regulation of PI3K/Akt signaling activation in A549 cancer cells.

Optogenetic control of epithelial-mesenchymal transition in cancer cells.

Epithelial-mesenchymal transition (EMT) is one of the most important mechanisms in the initiation and promotion of cancer cell metastasis. The phosphoinositide 3-kinase (PI3K) signaling pathway has been demonstrated to be involved in TGF-ß induced EMT, but the complicated TGF-ß signaling network makes it challenging to dissect the important role of PI3K on regulation of EMT process. Here, we applied optogenetic controlled PI3K module (named 'Opto-PI3K'), which based on CRY2 and the N-terminal of CIB1 (CIBN), to rapidly and reversibly control the endogenous PI3K activity in cancer cells with light. By precisely modulating the kinetics of PI3K activation, we found that E-cadherin is an important downstream target of PI3K signaling. Compared with TGF-ß treatment, Opto-PI3K had more potent effect in down-regulation of E-cadherin expression, which was demonstrated to be regulated in a light dose-dependent manner. Surprisingly, sustained PI3K activation induced partial EMT state in A549 cells that is highly reversible. Furthermore, we demonstrated that Opto-PI3K only partially mimicked TGF-ß effects on promotion of cell migration in vitro. These results reveal the importance of PI3K signaling in TGF-ß induced EMT, suggesting other TGF-ß regulated signaling pathways are necessary for the full and irreversible promotion of EMT in cancer cells. In addition, our study implicates the great promise of optogenetics in cancer research for mapping input-output relationships in oncogenic pathways.