Explorations of post-gDLI low-dose cyclophosphamide for preventing severe aGVHD.

OBJECTIVE: Relapse after allogeneic hematopoietic stem cell transplantation (allo-HSCT) is a serious life-threatening complication. The granulocyte colony-stimulated factor mobilized donor lymphocyte infusions (gDLI) combined with chemotherapy is currently a commonly used treatment method. Nevertheless, gDLI may cause so severe acute graft-versus-host disease (aGVHD) as to impact prognosis. Posttransplant cyclophosphamide (PTCy) has been the backbone for GVHD prophylaxis by inducing tolerance to minor histocompatibility antigens in recipients, while the application of post-gDLI low-dose cyclophosphamide (PDCy) for GVHD prophylaxis has not yet been attempted. METHODS: To explore this possibility, a retrospective study was conducted. 20 patients relapsing after HSCT were administered 20 mg/kg/d cyclophosphamide（Cy）on day 3 (for matched related transplantation) or on days 3 and 4 (for haplo-identical or unrelated transplantation) after gDLI to prevent aGVHD (the PDCy group). Furthermore, through propensity score matching, 58 matched controls received other (for HID and URD) or no (for MSD) immunosuppressive therapy for GVHD prophylaxis (the Non-Cy group). RESULTS: With a median follow-up of 4.8 (0-37.1) months, the PDCy group had lower cumulative incidence of severe aGVHD (III-IV, 5 % vs 31 %, p = 0.02; II-IV, 25 % vs 52 %, p = 0.04), but no significant differences existed in 4-month OS (64 % vs 59 %, p = 0.51), 4-month CIR (20 % vs 47 %, p = 0.11), rates of objective response (68.8 % vs 54.5 %, p = 0.6) (hematological or extramedullary relapse), MRD complete response (25 % vs 42 % p = 1) and MRD response (25 % vs 50 %, p = 0.6) (molecular relapse) between the PDCy group and the Non-Cy group. The PDCy regimen didn't increase the incidence of adverse infection, hemorrhagic cystitis, and cardiac events. CONCLUSION: On the premise of safety, the PDCy regimen could effectively protest against severe aGVHD after gDLI while preserving therapeutic response rates. However, the research results still require verification through longer follow-up and large prospective randomized studies.

Efficacy of venetoclax combined with decitabine conditioning regimen for allogeneic hematopoietic stem cell transplantation in high-risk and elderly patients with myeloid neoplasms.

This prospective clinical investigation focused on the addition of venetoclax and decitabine to myeloablative conditioning regimens, targeting high-risk and elderly individuals undergoing allogeneic hematopoietic stem cell transplantation. In total, 19 patients were enrolled in the trial between December 2021 and February 2023, and their progress was monitored for a median follow-up period of 258 days, ranging from 35 to 544 days. In the initial regimen (n=11), venetoclax was administered at a dosage of 400 mg per day from day -14 to day -1, while in the modified regimen (n=8), it was administered from day -14 to day -5. Decitabine was orally administered at a dosage of 20mg/m2/day from day -7 to day -3. Grade 3/4 adverse events observed included hematological events, hypertension, infections, allergy, and increased amylase. In the entire cohort, the overall survival (OS) and relapse-free survival (RFS) rates at 6 months were 63% (95% CI, 45-89) and 63% (95% CI, 45-89), respectively. The non-relapse mortality (NRM) rate at 6 months was 37% (95% CI, 16-58), while the cumulative incidence of relapse (CIR) was 0. However, the incidence of grade II-IV acute graft-versus-host disease (aGVHD) and grade III-IV aGVHD within 100 days was found to be 31% (95% CI, 12-53) and 26% (95% CI, 9-47), respectively. These rates indicate a relatively high occurrence, making it less suitable to administer the regimen to elderly patients. Therefore, further high-quality studies are required to enhance the conditioning regimen specifically for high-risk and elderly patients diagnosed with myeloid neoplasms. Clinical trial registration: ChiCTR2100050272.

A false positive serology test of SARS­CoV­2 in a patient with Waldenström's macroglobulinemia: A case report.

The serology test of SARS-CoV-2 is one of the critical assays to make a diagnosis of SARS-CoV-2 infection. The gold immunochromatography assay (GICA) is a common measure to test SARS-CoV-2 specific IgG and IgM. The sensitivity and specificity of the assay are ~>80%. It has been reported that the result of GICA could be compromised in various situations, such as auto-immune diseases, Kawasaki disease, pregnancy or other conditions. However, following the European Hematology Association's consensus statement on the management of Waldenström's Macroglobulinemia (WM) patients, serological tests for SARS-CoV-2 specific IgM should not be affected by the total IgM or paraprotein levels. The present study reports a patient with duplicate positive serology tests of SARS-CoV-2 which is hypothesized to be due to monoclonal IgM caused by WM.

Carotid plaque score and ischemic stroke risk stratification through a combination of B-mode and contrast-enhanced ultrasound in patients with low and intermediate carotid stenosis.

Objective: The occurrence of ischemic stroke (IS) is closely related to the characteristics of carotid plaque (CP). Due to the effect of stroke risk stratification based on B-mode ultrasound (US) and contrast-enhanced ultrasound (CEUS) that has not been studied in patients with low and intermediate carotid stenosis, we construct and validate a CP score and ischemic stroke risk stratification (ISRS) using a combination of B-mode and CEUS, in order to provide new convenient strategies to stratify these patients to prevent stroke. Materials and methods: This retrospective study evaluated 705 patients with low and intermediate carotid stenosis who underwent B-mode and CEUS from November 2021 to April 2023. Qualitative B-mode and CEUS features of carotid plaques were analyzed using a univariable and multivariable logistic regression to construct the CP score. Then, we combined the CP score with Essen stroke risk score (ESRS) to develop ISRS. Results: This study included a total of 705 patients with low and intermediate carotid stenosis, of which 394 were symptomatic patients (with a mean age of 71.03 ± 10.48 years) and 311 were asymptomatic patients (with a mean age of 65.13 ± 10.31 years). Plaque echogenicity, plaque morphology, carotid intima-media thickness in B-mode US and intraplaque neovascularization grading and perfusion pattern in CEUS were significantly associated with IS. The ISRS incorporating these five predictors and ESRS showed good discrimination and calibration in both primary cohort [area under the curve (AUC), 0.91; Hosmer-Lemeshow test, p = 0.903] and validation cohort (AUC, 0.84; Hosmer-Lemeshow test, p = 0.886). Conclusion: We developed an effective and practical tool to identify and stratify patients with low and intermediate carotid stenosis, based on the CP score and ISRS estimation. Our study may provide new insights into managing patients with no indication of surgery.

Vancomycin, Daptomycin, Antistaphylococcal ß-Lactam, and Trimethoprim-Sulfamethoxazole Monotherapy and Combination Therapy in the Management of Methicillin-Resistant Staphylococcus aureus: A Network Meta-Analysis.

Objective: The aim was to evaluate the efficacy and safety of vancomycin or daptomycin (VAN/DAP), antistaphylococcal ß-lactam (ASBL), trimethoprim-sulfamethoxazole (TMP-SMX), and combination therapy of VAN/DAP + ASBL in the management of methicillin-resistant Staphylococcus aureus (MRSA). Methods: Databases including PubMed, Cochrane Library, Embase database, and google scholar were searched on 1 September 2021. The randomized control trials (RCTs) and comparable clinical studies of VAN/DAP, VAN/DAP + ASBL, ASBL, and TMP-SMX in the management of MRSA were identified. A network meta-analysis was conducted with STATA 14.0. Results: Seven RCTs and two matched cohorts with 1,048 patients were included in the analysis. The pooled results showed that VAN/DAP + ASBL had a significantly lower rate of persistent bacteremia >3 days than VAN/DAP alone [OR:0.46, 95%CI (0.26, 0.81), p < 0.001]. No obvious differences were observed in the outcomes of all-cause mortality, relapsed bacteremia, microbiological treatment failure, embolic or metastatic infection, and total adverse events. However, the ranking results showed that VAN/DAP + ASBL had slightly better efficacy (all-cause mortality, persistent bacteremia >3 days, duration of bacteremia, microbiological treatment failure, and relapsed bacteremia) but slightly higher adverse events than VAN/DAP alone. No obvious differences in the comparisons of VAN/DAP vs. ASBL, and VAN/DAP vs TMP-SMX in the analyzed outcomes. The ranking results revealed that ASBL and TMP-SMX did not have better efficacy or lower adverse events compared with the treatment of VAN/DAP. Conclusion: The efficacy of VAN/DAP + ASBL was slightly but not significantly better than VAN/DAP alone in the management of MRSA.

Cause of death of patients with non-muscular invasive, non-metastatic muscular invasive and metastatic bladder cancer after diagnosis.

BACKGROUND: The purpose of this study was to evaluate the various causes of death among patients with non-muscular invasive bladder cancer (NMIBC), non-metastatic muscle invasive bladder cancer (non-MMIBC) and metastatic bladder cancer (MBC) after diagnosis. METHODS: With the Surveillance, Epidemiology, and Final Results database, patients diagnosed with bladder cancer from 2004 to 2015 were identified. All causes of death and the standardization mortality ratio (SMR) were analyzed. RESULTS: A total of 111,784 NMIBC, 26,546 non-MIBC and 4,678 MBC patients were identified. For NMIBC patients, 44,638 patients died during the follow-up, including 20.57% of bladder cancer, 18% of other tumors and 61.36% of non-tumor diseases. Main causes of other tumors death were cancers from lung and bronchus [n=2,860, SMR: 1.56 (1.51-1.62)], pancreas [n=506, SMR: 1.15 (1.05-1.26)], and prostate [n=442, SMR: 0.62 (0.56-0.68)]. Main causes of non-tumor deaths were diseases of heart [n=10,007, SMR: 1.15 (1.13-1.17)], chronic obstructive pulmonary disease (COPD) [n=3,153, SMR: 1.54 (1.49-1.59)], cerebrovascular diseases [n=1,704, SMR: 0.96 (0.91-1)], alzheimers [n=1,211, SMR: 0.87 (0.82-0.92)] and diabetes mellitus [n=1,047, SMR: 1.19 (1.12-1.27)]. Among the 18829 deaths in non-MMIBC patients, 62.65% patients died of bladder cancer, 11.08% of other tumors and 26.39% of non-tumor causes. Main deaths of other cancers were tumors from lung and bronchus [n=435, SMR: 1.83 (1.66-2.01)], prostate [n=192, SMR: 2.21 (1.91-2.54)]. Main causes of non-tumor death were diseases of heart [n=1717, SMR: 1.56 (1.49-1.64)], COPD [n=561, SMR: 2.18 (2.01-2.37)], and cerebrovascular diseases [n=290, SMR: 1.28 (1.14-1.44)]. Among the 4,392 deaths of MBC patients, 3,486 (79.37%) died of bladder cancer. Main cause of other deaths included diseases of heart (n=128) and prostate cancer (n=57). CONCLUSION: For NMIBC patients, leading causes of death were diseases of heart, COPD, lung and bronchus cancer, cerebrovascular diseases, Alzheimer's, and diabetes mellitus. Leading causes of deaths for non-MMIBE patients were bladder cancer, diseases of heart, COPD, lung and bronchus cancer, cerebrovascular diseases and prostate cancer. Main causes of death for MBC patients were bladder cancer itself. Our results of all causes of death and mortality risks provided useful information for bladder cancer patients.

Impact of changes in psychological resilience during treatment with intensity-modulated radiotherapy on nasopharyngeal carcinoma patients: a prospective study.

BACKGROUND: Nasopharyngeal carcinoma (NPC) patients can undergo changes in psychological status during treatment. The aim of this prospective study was to determine the impact of the changes in psychological resilience on the quality of life (QoL) and long-term outcomes of patients. METHODS: Patients with NPC receiving intensity-modulated radiotherapy (IMRT) between March 2017 and February 2019 were prospectively included. Their psychological resilience was evaluated by the Connor-Davidson resilience scale (CD-RISC) twice. Patients were then divided into the improved psychological resilience group and the deteriorated group. All patients were followed up for at least 2 years, and acute or late severe complications were recorded. The QoL of patients was evaluated within 1 year by the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30-questions (QLQ-C30) and the Head and Neck 35-questions (HN35). Logistic regression analysis was used for the analysis of risk factors of psychological resilience in NPC patients. Similarly, linear regression analysis was used for the analysis of risk factors of QoL in NPC patients. The overall survival rate and progression-free survival rate were recorded and compared between the 2 groups using Kaplan-Meier curves. RESULTS: A total of 180 patients were included. The mean CD-RISC scores before radiotherapy and after radiotherapy were 55.8±7.0 and 58.4±7.8 points, respectively. Patients were divided into 104 patients in the improved group and 76 patients in the deteriorated group. Older age, advanced stage, chemotherapy treatment, and severe complications were important risk factors according to the multivariable logistic regression analysis. There were no significant differences in QLQ-C30 and HN35 scores before radiotherapy between the 2 groups, while significant differences were found in most items in the QLQ-C30 and HN35 between the 2 groups. Deteriorated resilience was identified as an important risk factor of QoL according to the multivariable linear regression analysis. NPC patients had significantly higher overall survival and progression-free survival in the improved group than in the deteriorated group. CONCLUSIONS: Psychological resilience has an important impact on the prognosis of NPC patients, thus more attention should be paid to their psychological status during treatment with radiotherapy.

Transperitoneal versus retroperitoneal approaches of pyeloplasty in management of ureteropelvic junction obstruction: A meta-analysis.

The aim of this study was to evaluate the benefits and safety of transperitoneal and retroperitoneal pyeloplasty for ureteropelvic junction obstruction by a meta-analysis. We searched the databases including PubMed, Cochrane Library and Embase database from their inception to December 1st, 2020. Relevant literatures comparing retroperitoneal pyeloplasty with transperitoneal pyeloplasty were identified. A meta-analysis was conducted with Revman 5.3. The main outcomes included success rate, operative time, hospital stay, conversion rate of open surgery, overall complications, and detailed postoperative complications/indicators. 15 studies with 1881 patients were included. The results revealed that there were no significant differences between two approaches in success rate [OR = 1.51, 95%CI (0.94, 2.41), p = 0.09], hospital stay [MD = 0.21, 95%CI (-0.12, 0.54), p = 0.21] and overall complications [OR = 1.07, 95%CI (0.76, 1.50), p = 0.69]. The retroperitoneal approach was associated with longer operative time [MD = -26.91, 95%CI (-40.97, -12.84), p < 0.001], higher conversion rate [OR = 0.23, 95%CI (0.11, 0.47), p < 0.001] than the transperitoneal approach. As for the detailed postoperative complications/indicators, there were no significant differences between two approaches in the urinary leak, mild hematuria, fever, UPJO recurrence, infection and subcutaneous emphysema, as well as split renal function, renal pelvis anteroposterior diameter. The funnel plots showed that there were no obvious publication biases in our analysis. Therefore, we concluded that transperitoneal and retroperitoneal approaches had similar benefits and safety in success rate, hospital stay, overall complications and detailed postoperative complications/indicators. However, retroperitoneal was associated with longer operative time and higher conversion rate than transperitoneal approach. With the limitations of our study, additional high-quality studies are still essential for further evaluation.

The Impact of Palliative Transurethral Resection of the Prostate on the Prognosis of Patients With Bladder Outlet Obstruction and Metastatic Prostate Cancer: A Population-Matched Study.

Objective: This study aimed to evaluate the survival outcomes of patients with bladder outlet obstruction (BOO) and metastatic prostate cancer (mPCa) after having a palliative transurethral resection of the prostate (pTURP) surgery. Methods: We identified patients with mPCa between 2004 and 2016 in the Surveillance, Epidemiology, and End Results (SEER) database. Patients who received pTURP and non-surgical therapy were identified. A propensity-score matching was introduced to balance the covariate. Kaplan-Meier analysis and COX regression were conducted to evaluate the overall survival (OS) and cancer-specific survival (CSS) outcomes. Results: A total of 36,003 patients were identified; 2,823 of them were in the pTURP group and 33,180 were in the non-surgical group. The survival curves of the overall cohort showed that the pTURP group was associated with worse outcomes in both OS (HR: 1.12, 95% CI: 1.07-1.18, p < 0.001) and CSS (HR: 1.08, 95% CI: 1.02-1.15, p = 0.004) compared with the non-surgical group. The mean survival time in the overall cohort of the pTURP group was shorter than the non-surgical group in both OS [35.13 ± 1.53 vs. 40.44 ± 0.59 months] and CSS [48.8 ± 1.27 vs. 55.92 ± 0.43 months]. In the matched cohort, the pTURP group had significantly lower survival curves for both OS (HR: 1.25, 95% CI: 1.16-1.35, p < 0.001) and CSS (HR: 1.23, 95% CI: 1.12-1.35, p < 0.001) than the non-surgical group. pTURP significantly reduced the survival months of the patients (36.49 ± 0.94 vs. 45.52 ± 1.23 months in OS and 50.1 ± 1.49 vs. 61.28 ± 1.74 months in CSS). In the multivariate COX analysis, pTURP increased the risk of overall mortality (HR: 1.19, 95% CI: 1.09-1.31, p < 0.001) and cancer-specific mortality CSS (HR: 1.23, 95% CI: 1.14-1.33, p < 0.001) compared with the non-surgical group. Conclusions: For mPCa patients with BOO, pTURP could reduce OS and CSS while relieving the obstruction.

Laparoscopic treatment of a series of rare tumors, gastric schwannoma with chronic iron deficiency anemia: A case report.

INTRODUCTION AND IMPORTANCE: Gastric schwannoma is a rare and slow-growing gastrointestinal mesenchymal tumor. Gastric neurilemmoma accounts for less than 1% of all gastric tumors. Without specific clinical manifestations, it is easy to be misdiagnosed before the operation, and rupture and bleeding will lead to persistent anemia in patients. The diagnosis can only be confirmed by pathological examination. CASE PRESENTATION: A 55-year-old woman was admitted to The Second Hospital of Lanzhou University due to abdominal distension, pain, acid regurgitation, and belching. The tumor was completely removed by laparoscopy. The postoperative specimens were diagnosed as gastric neurilemmoma by pathological examination. CLINICAL DISCUSSION: Schwannoma is a benign neurogenic tumor. Complete surgical resection with a negative cutting edge is an effective method for the treatment of gastric schwannoma. Because the lesion is benign, the prognosis of the patient is good. CONCLUSION: Laparoscopic tumor resection is a choice for the treatment of gastric schwannoma, and the therapeutic effect is good.

First-in-Human Phase I Study of Envafolimab, a Novel Subcutaneous Single-Domain Anti-PD-L1 Antibody, in Patients with Advanced Solid Tumors.

LESSONS LEARNED: Subcutaneous injection was an effective route of administration for envafolimab with a favorable pharmacokinetic profile in patients with previously treated advanced solid tumors. Subcutaneous envafolimab was well tolerated and had durable antitumor activity at a wide range of doses and schedules. Envafolimab has the potential to be a more convenient option than currently approved intravenous PD-1/PD-L1 inhibitors. BACKGROUND: Envafolimab is a novel fusion of a humanized single-domain PD-L1 antibody and human IgG1 Fc fragment formulated for subcutaneous injection. This study explored the safety and feasibility of subcutaneous administration of envafolimab as an alternative to intravenous administration of PD-1/PD-L1 inhibitors in the treatment of advanced, refractory solid tumors. METHODS: This was a first-in-human, open-label phase I trial. In a dose-escalation phase, patients received subcutaneous envafolimab 0.01-10 mg/kg once weekly following a modified 3+3 design. In a dose-exploration phase, patients received subcutaneous envafolimab 300 mg once every 4 weeks. RESULTS: Twenty-eight patients were enrolled (dose escalation n = 18, dose exploration n = 10, median age 66 years; 71% male; ECOG performance score = 0 [21%] or 1 [79%]). No dose-limiting toxicities or injection-site reactions were reported. Envafolimab demonstrated dose-proportional increases in area under the time-concentration curve and maximum plasma concentration. Median time to maximum plasma concentration was 4-7 days. In the dose-exploration phase, terminal half-life was 14 days after dose 1 in cycle 1 and 23 days at steady state. Three patients experienced a confirmed partial response. CONCLUSION: Subcutaneous envafolimab had a favorable safety and pharmacokinetic profile, with promising preliminary antitumor activity in patients with advanced solid tumors.

Discovery of a New Four-Leaf Clover-Like Ligand as a Potent c-MYC Transcription Inhibitor Specifically Targeting the Promoter G-Quadruplex.

Downregulating transcription of the oncogene c-MYC is a feasible strategy for cancer therapy. Stabilization of the G-quadruplex structure present in the c-MYC promoter can suppress c-MYC transcription. Thus, far, several ligands targeting this structure have been developed. However, most have shown no selectivity for the c-MYC G-quadruplex over other G-quadruplexes, leading to uncertain side effects. In this study, through structural modification of aryl-substituted imidazole/carbazole conjugates, a brand-new, four-leaf clover-like ligand called IZCZ-3 was found to preferentially bind and stabilize the c-MYC G-quadruplex. Further intracellular studies indicated that IZCZ-3 provoked cell cycle arrest and apoptosis and thus inhibited cell growth, primarily by blocking c-MYC transcription through specific targeting of the promoter G-quadruplex structure. Notably, IZCZ-3 effectively suppressed tumor growth in a mouse xenograft model. Accordingly, this work provides an encouraging example of a selective small molecule that can target one particular G-quadruplex structure, and the selective ligand might serve as an excellent anticancer agent.

MicroRNA-99a inhibits insulin-induced proliferation, migration, dedifferentiation, and rapamycin resistance of vascular smooth muscle cells by inhibiting insulin-like growth factor-1 receptor and mammalian target of rapamycin.

Patients with type 2 diabetes mellitus (T2DM) are characterized by insulin resistance and are subsequently at high risk for atherosclerosis. Hyperinsulinemia has been associated with proliferation, migration, and dedifferentiation of vascular smooth muscle cells (VSMCs) during the pathogenesis of atherosclerosis. Moreover, insulin-like growth factor-1 receptor (IGF-1R) and mammalian target of rapamycin (mTOR) have been demonstrated to be the underlying signaling pathways. Recently, microRNA-99a (miR-99a) has been suggested to regulate the phenotypic changes of VSMCs in cancer cells. However, whether it is involved in insulin-induced changes of VSCMs has not been determined. In this study, we found that insulin induced proliferation, migration, and dedifferentiation of mouse VSMCs in a dose-dependent manner. Furthermore, the stimulating effects of high-dose insulin on proliferation, migration, and dedifferentiation of mouse VSMCs were found to be associated with the attenuation of the inhibitory effects of miR-99a on IGF-1R and mTOR signaling activities. Finally, we found that the inducing effect of high-dose insulin on proliferation, migration, and dedifferentiation of VSMCs was partially inhibited by an active mimic of miR-99a. Taken together, these results suggest that miR-99a plays a key regulatory role in the pathogenesis of insulin-induced proliferation, migration, and phenotype conversion of VSMCs at least partly via inhibition of IGF-1R and mTOR signaling. Our results provide evidence that miR-99a may be a novel target for the treatment of hyperinsulinemia-induced atherosclerosis.

[Effect of lycium bararum polysaccharides on angiotensin II-induced senescence of human umbilical vein endothelial cells and expressions of P53 and P16].

OBJECTIVE: To investigate the role of lycium bararum polysaccharides (LBP) on angiotensin II (AngII)-induced senescence of human umbilical vein endothelial cells (HUVECs) and expressions of P53 and P16 and explore the mechanism of LBP against aging. METHODS: HUVECs cultured in vitro were stimulated with 1×10(-6) mmol/L AngII to induce cell senescence, which was identified using ß-gal staining. Flow cytometry was used for analyzing the cell cycle changes, and the cell viability was assessed using CCK-8 method. Western blotting was employed to detect the expression of P53 and P16 in the exposed cells. RESULTS: Compared with the control cells, the cells positive for ß-gal staining was significantly increased in AngII group, and showed cell cycle arrest at G(0)/G(1) phase with decreased S-phase cell percentage and cell viability. The expression levels of P53 and P16 were significantly increased in the cells with AngII exposure (P<0.05). LBP treatment of AngII-exposed cells resulted in decreased ß-gal-positive cells with a reduction in G(0)/G(1) phase cells and an increase in S phase cells. LBP treatment also increased the cell viability and significantly decreased the expression levels of P53 and P16 (P<0.05). CONCLUSION: LBP can delay AngII-induced aging of HUVECs possibly by down-regulating the expression of P53 and P15.

A new long form of c-Maf cooperates with Sox9 to activate the type II collagen gene.

A new long form of the c-Maf transcription factor (Lc-Maf) was identified and shown to interact specifically with SOX9 in a yeast two-hybrid cDNA library screening. Lc-Maf encodes an extra 10 amino acids at the carboxyl terminus of c-Maf and contains a different 3'-untranslated region compared with c-Maf. The interaction between SOX9 and Lc-Maf was further confirmed by co-immunoprecipitation and glutathione S-transferase pull-down assays, which mapped the interacting domain of SOX9 to the high mobility group box DNA binding domain and that of Lc-Maf to the basic leucine zipper motif. In situ hybridizations showed that Lc-Maf RNA was coexpressed with Sox9 and Col2a1 RNA in areas of precartilaginous mesenchymal condensations during mouse embryo development. A DNA binding site of Lc-Maf was identified at the 5'-end of a 48-bp Col2a1 enhancer element near the high mobility group binding site of SOX9. Lc-Maf and SOX9 synergistically activated a luciferase reporter plasmid containing a Col2a1 enhancer and increased the transcription of the endogenous Col2a1 gene. In summary, Lc-Maf is the first transcription factor shown to interact with Sox9, to be coexpressed with Sox9 during an early step of chondrogenesis and to cooperate with Sox9 in activating a downstream target gene of Sox9.