Predicting recurrence and survival in patients with non-metastatic renal-cell carcinoma after nephrectomy: a prospective population-based study with multicenter validation.

BACKGROUND: Accurate prognostication of oncological outcomes is crucial for the optimal management of patients with renal cell carcinoma (RCC) after surgery. Previous prediction models were developed mainly based on retrospective data in the Western populations, and their predicting accuracy remains limited in contemporary, prospective validation. We aimed to develop contemporary RCC prognostic models for recurrence and overall survival (OS) using prospective population-based patient cohorts and compare their performance with existing, mostly utilized ones. METHODS: In this prospective analysis and external validation study, the development set included 11  128 consecutive patients with non-metastatic RCC treated at a tertiary urology center in China between 2006 and 2022, and the validation set included 853 patients treated at 13 medical centers in the USA between 1996 and 2013. The primary outcome was progression-free survival (PFS), and the secondary outcome was OS. Multivariable Cox regression was used for variable selection and model development. Model performance was assessed by discrimination [Harrell's C-index and time-dependent areas under the curve (AUC)] and calibration (calibration plots). Models were validated internally by bootstrapping and externally by examining their performance in the validation set. The predictive accuracy of the models was compared with validated models commonly used in clinical trial designs and with recently developed models without extensive validation. RESULTS: Of the 11  128 patients included in the development set, 633 PFS and 588 OS events occurred over a median follow-up of 4.3 years [interquartile range (IQR) 1.7-7.8]. Six common clinicopathologic variables (tumor necrosis, size, grade, thrombus, nodal involvement, and perinephric or renal sinus fat invasion) were included in each model. The models demonstrated similar C-indices in the development set (0.790 [95% CI 0.773-0.806] for PFS and 0.793 [95% CI 0.773-0.811] for OS) and in the external validation set (0.773 [0.731-0.816] and 0.723 [0.731-0.816]). A relatively stable predictive ability of the models was observed in the development set (PFS: time-dependent AUC 0.832 at 1 year to 0.760 at 9 years; OS: 0.828 at 1 year to 0.794 at 9 years). The models were well calibrated and their predictions correlated with the observed outcome at 3, 5, and 7 years in both development and validation sets. In comparison to existing prognostic models, the present models showed superior performance, as indicated by C-indices ranging from 0.722 to 0.755 (all P <0.0001) for PFS and from 0.680 to 0.744 (all P <0.0001) for OS. The predictive accuracy of the current models was robust in patients with clear-cell and non-clear-cell RCC. CONCLUSIONS: Based on a prospective population-based patient cohort, the newly developed prognostic models were externally validated and outperformed the currently available models for predicting recurrence and survival in patients with non-metastatic RCC after surgery. The current models have the potential to aid in clinical trial design and facilitate clinical decision-making for both clear-cell and non-clear-cell RCC patients at varying risk of recurrence and survival.

Seminoma arising in splenogonadal fusion: a case report and literature review.

BACKGROUND: Splenogonadal fusion (SGF) is a rare congenital malformation in which the spleen is abnormally connected to the gonads or to the mesonephric derivatives. There is no obvious causality between SGF and testicular neoplasm. However, cryptorchidism, which is a well-known risk factor of testicular germ cell tumors, are the most frequent malformations associated with SGF. To our knowledge, there are only four reported cases of SGF associated with testicular neoplasm so far. Herein, we reported a patient of this condition, and briefly reviewed the related literature. CASE PRESENTATION: A 48-year-old man was diagnosed with bilateral cryptorchidism 30 years prior, and only underwent a right orchiopexy for the left testicle could not be explored during the operation. At that time, doctors failed to realize the possibility of SGF due to the lack of sufficient knowledge of this condition. This time, the patient was treated for a left abdomen mass that was diagnosed as stage III metastatic seminoma. Then, a right orchiectomy, robot-assisted laparoscopic left retroperitoneal tumor resection, and left retroperitoneal lymph node dissection was performed after four cycles of BEP (bleomycin + etoposide + cisplatin) systemic chemotherapy in our center. The final diagnosis of SGF was made by postoperative pathology. The patient was re-examined in our center at 3 months and 6 months after the operation, and no obvious abnormalities were found. CONCLUSIONS: Surgeons should always bear in mind the possibility of association between bilateral cryptorchidism and splenogonadal fusion to avoid malignant transformation caused by delayed treatment.

Mutational signature and clonal relatedness of recurrent urothelial carcinomas with aristolochic acid.

Urothelial carcinomas (UCs) are malignant tumors that arise from the lower and upper urinary tract and are characterized by multiple recurrences. Aristolochic acid (AA) is a potent nephrotoxin and human carcinogen associated with UC. East Asian populations with a high UC prevalence have an unusual genome-wide AA-induced mutational pattern. To address the genomic differences and clonal relatedness between primary and recurrent tumors in the UCs with AA pattern, we investigated the genomic differences and tumor microenvironment (TME) of AA and non-AA UCs. 17 UC patients were recruited, with nine documented AA exposure. Eleven of them showed recurrence. After-surgery tissues of primary and paired recurrent tumors were collected. Capture-based targeted deep sequencing was performed using a commercial panel consisting of 520 cancer-related genes. Tumor-infiltrating lymphocytes (TILs) were identified with an immunofluorescence-based microenvironment analysis panel (MAP). Hierarchical clustering based on the COSMIC signatures confirmed two significant subtypes: AA Sig and non-AA Sig. AA Sig was associated with AA-containing herbal drug intake, recurrence, and higher tumor mutation burden (TMB). The clonal architecture of UCs revealed three types of clonal evolution patterns. Non-AA Sig cohort showed shared clonal origin of primary and recurrent tumors. AA Sig showed heterogeneity and had multiple independent origins. Recurrent tumors as second primary tumors in AA Sig showed immunoreactive TME, indicating a better response with immune checkpoint inhibitor therapy. The AA mutational signature and unique immune profiles are helpful molecular markers to distinguish AA exposure from other carcinogens. These results also provide new insights into the origin of recurrent UCs that could affect treatment strategies.

Loss of cell division cycle­associated 5 promotes cell apoptosis by activating DNA damage response in clear cell renal cell carcinoma.

Cell division cycle­associated 5 (CDCA5) protein, which is involved in cohesion, contributes to cell cycle regulation and chromosome segregation by maintaining genomic stability. Accumulating evidence indicates that CDCA5 expression is upregulated in a number of types of cancer associated with a poor prognosis. However, the biological function of CDCA5 in clear cell renal cell carcinoma (ccRCC) remains largely unknown. In the present study, The Cancer Genome Atlas data mining revealed that CDCA5 was more highly expressed in ccRCC than in adjacent normal tissues. Importantly, such a high expression was associated with a higher risk of distant metastasis and poorer clinical outcomes. Moreover, the clinical and prognostic value of CDCA5 expression was further investigated using immunohistochemistry on tissue microarrays containing paired tumor tissues and adjacent normal tissues from 137 patients with ccRCC. Functional analyses revealed that CDCA5 knockdown significantly inhibited the proliferation and migration of ccRCC cells, and suppressed the growth of xenografts in nude mice. Mechanistically, CDCA5 knockdown induced severe DNA damage with the persistent accumulation of γ­H2A histone family member X foci, resulting in G2/M cell cycle arrest and finally, in chromosomal instability and apoptosis. CDCA5 knockdown significantly decreased the phosphorylation levels of Stat3 and NF­κB, suggesting that CDCA5 plays a role in regulating the inflammatory response. Collectively, the findings of the present study indicate that ccRCC cells require CDCA5 for malignant progression, and that CDCA5 inhibition may enhance the outcomes of patients with high­risk ccRCC.

Robot-Assisted Kidney Transplantation: Initial Experience with a Modified Hypothermia Technique.

INTRODUCTION: The aim of the study was to report our initial experience of robot-assisted kidney transplantation (RAKT) with a modified hypothermia technique. METHODS: Between March 2018 and May 2020, 12 patients with end-stage renal disease underwent RAKT at the Chinese PLA General Hospital, and a modified regional hypothermia was implemented by wrapping the kidney in a sealed plastic jacket filled with ice slush. Baseline, surgical, and functional outcomes were analyzed. RESULTS: All surgeries were successfully performed. The mean operative time was 180.5 min, with a mean console time of 133.3 min. Mean warm ischemia, cold ischemia, and rewarming times were 1.5, 135.1, and 48.4 min, respectively. The median blood loss was 50 mL, and the median hospital stay was 9.5 days. No complications were observed. The mean serum creatinine levels were 119.4, 100.5, 108, and 108.5 µmol/L 7 days, 1 month, 6 months, and 1 year postoperatively, respectively. All patients and grafts survived at a median follow-up of 32.2 months. CONCLUSION: RAKT is a safe and feasible procedure for surgical teams with expertise in open kidney transplantation and robotic surgery. Our modification of the hypothermia technique can maintain the kidney at a constant low temperature without repeatedly adding ice and prevent the complication of paralytic ileus.

Loss of CMTM6 promotes DNA damage-induced cellular senescence and antitumor immunity.

Recent studies have revealed that chemokine-like factor-like MARVEL transmembrane domain-containing family member 6 (CMTM6) promotes tumor progression and modulates tumor immunity by regulating programmed death-ligand 1 stability; however, its intrinsic functions and regulatory mechanisms in clear cell renal cell carcinoma (ccRCC) remain poorly understood. Here, we show that CMTM6 is upregulated in ccRCC tissues and is strongly associated with advanced tumor grades, early metastases, and a worse prognosis. CMTM6 depletion significantly impaired the proliferation, migration, and invasion of ccRCC cells in vitro and in xenograft mouse models in vivo. In addition, targeting CMTM6 promotes anti-tumor immunity, represented by increased infiltration of CD4+ and CD8+ T cells in syngeneic graft mouse models. Further research revealed that loss of CMTM6 triggered aberrant activation of DNA damage response, resulting in micronucleus formation and G2/M checkpoint arrest, finally leading to cellular senescence with robust upregulation of numerous chemokines and cytokines. Our findings show for the first time the novel role of CMTM6 in maintaining cancer genome stability and facilitating tumor-mediated immunosuppression, linking DNA damage signaling to the secretion of inflammatory factors. Targeting CMTM6 may improve the treatment of patients with advanced ccRCC.

E2F1 promotes proliferation and metastasis of clear cell renal cell carcinoma via activation of SREBP1-dependent fatty acid biosynthesis.

Enhanced synthesis or uptake of lipids contributes to rapid cancer cell proliferation and tumor progression. In recent years, cell cycle regulators have been shown to be involved in the control of lipid synthesis, in addition to their classical function of controlling the cell cycle. Clear cell renal cell carcinoma (ccRCC) is the most common subtype of kidney cancer and is characterized by lipid-rich cytoplasmic deposition. However, the relationship between altered lipid metabolism and tumor progression in ccRCC is poorly understood. Here, we demonstrated that E2F transcription factor 1 (E2F1), in addition to its key role in regulating the cell cycle, induces extensive lipid accumulation and elevated levels of lipogenic enzymes in ccRCC cells by upregulating sterol regulatory element-binding protein 1 (SREBP1). E2F1 knockdown or SREBP1 suppression attenuated fatty acid (FA) de novo synthesis, cell proliferation and epithelial-mesenchymal transition (EMT) in ccRCC cells. Furthermore, overexpression of E2F1 promoted lipid storage, tumor growth and metastasis in a mouse xenograft model, whereas E2F1 downregulation or SREBP1 inhibition reversed these effects. In ccRCC patients, high levels of E2F1 and SREBP1 were associated with increased lipid accumulation and correlated with poor prognosis. Our results demonstrate that E2F1 can increase proliferation and metastasis through SREBP1-induced aberrant lipid metabolism, which is a novel critical signaling mechanism driving human ccRCC progression.

Prognostic role of bland thrombus in patients treated with resection of renal cell carcinoma with inferior vena cava tumor thrombus.

OBJECTIVES: To assess the impact of the presence of bland thrombus (BT) on prognosis of patients treated with resection of renal cell carcinoma (RCC) with inferior vena cava tumor thrombus (IVCTT). MATERIALS AND METHODS: The medical records of a total of 145 consecutive postsurgical RCC patients with level I-IV IVCTT were reviewed from January 2008 to August 2018. Associations of BT with clinicopathological variables were estimated by chi-square test or Student's t-test. Kaplan-Meier method and multivariate Cox proportional hazard model were used. The eighth TNM staging system, "Spiess PE" model, University of California at Los Angeles Integrated Staging System and Stage, Size, Grade, and Necrosis (SSIGN) score were selected to assess whether BT could improve their predictive abilities. RESULTS: BT was observed in 34 (23.4%) patients and was significantly associated with increased levels of IVCTT (P = 0.004) and invasion of IVC wall (P = 0.030). Multivariable Cox analyses revealed that tumor grade, T stage, M stage, tumor thrombus consistency and BT were independent risk factors for both progression-free survival and overall survival. The concordance indexes ranged from a low of 0.652 in TNM to a high of 0.731 in SSIGN, and integrating BT into each base model led to an increased predictive accuracies of 6.2% for TNM (P = 0.025), 4.0% for "Spiess PE" model (P = 0.069), 2.1% for University of California at Los Angeles Integrated Staging System (P = 0.149) and 1.2% for SSIGN (P = 0.290), respectively. CONCLUSIONS: Presence of BT was independently associated with survival in postsurgical patients with RCC-IVCTT. Routine consideration of BT as an adjunct to TNM staging system may be suggested.

Comparison of Transperitoneal and Retroperitoneal Robotic Partial Nephrectomy for Patients With Complete Upper Pole Renal Tumors.

OBJECTIVES: We compared the outcomes of transperitoneal robotic partial nephrectomy (TRPN) and retroperitoneal robotic partial nephrectomy (RRPN) for complete upper pole renal masses (1 point for the "L" component of the RENAL scoring system). MATERIAL AND METHODS: We retrospectively reviewed patients who underwent either TRPN or RRPN from 2013 to 2016. Baseline demographics and perioperative, functional, and oncological results were compared. Multivariable analysis was performed to identify factors related to pentafecta achievement (ischemia time ≤25 min, negative margin, perioperative complication free, glomerular filtration rate (eGFR) preservation >90%, and no chronic kidney disease upstaging). RESULTS: No significant differences between TRPN vs. RRPN were noted for operating time (110 vs. 114 min, p = 0.870), renal artery clamping time (19 vs. 18 min, p = 0.248), rate of positive margins (0.0% vs. 3.3%, p = 0.502), postoperative complication rates (25.0% vs. 13.3%, p = 0.140). TRPN was associated with a more estimated blood loss (50 vs. 40 ml, p = 0.004). There were no significant differences in pathologic variables, rate of eGFR decline for postoperative 12-month (9.0% vs. 7.1%, p = 0.449) functional follow-up. Multivariate analysis identified that only RENAL score (odd ratio: 0.641; 95% confidence interval: 0.455-0.904; p = 0.011) was independently associated with the pentafecta achievement. CONCLUSIONS: For completely upper pole renal masses, both TRPN and RRPN have good and comparable results. Both surgical approaches remain viable options in the treatment of these cases.

Androgen receptor modulates metastatic routes of VHL wild-type clear cell renal cell carcinoma in an oxygen-dependent manner.

Recent studies indicated that the androgen receptor (AR) plays important roles in modulating metastasis of VHL-mutant clear cell renal cell carcinoma (ccRCC). However, the precise mechanisms of AR roles in VHL wild-type (VHL-wt) ccRCC, remain unclear. Here we found that AR interacted with VHL to modulate the metastasis of VHL-wt ccRCC via an oxygen-dependent manner. Mechanism dissection revealed that AR could transcriptionally suppress the miR-185-5p expression in the presence of functional VHL-wt protein under a normoxic condition, which might then result in increasing the expression of VEGF-A and VEGF-C via targeting the 3'UTR of mRNAs at a post-transcriptional level. In contrast, under a hypoxic condition, AR could increase miR-185-5p expression to suppress VEGF-C expression, yet this miR-185-5p effect on VEGF-A was reversed via AR's positive regulation on the HIF2α-increased VEGF-A expression that resulted in increasing VEGF-A in the VHL-wt RCC cells. These distinct AR functions under different oxygen conditions may involve the VHL-impacted ubiquitination and nuclear localization of AR. The differential regulation of VEGF-A vs VEGF-C by AR may then result in differential impacts on the ccRCC metastatic destinations of VHL-wt ccRCC cells under different oxygen conditions. These finer mechanisms may help in the development of a novel therapy to better suppress the ccRCC progression under different oxygenization conditions.

A modified sequential vascular control strategy in robot-assisted level III-IV inferior vena cava thrombectomy: initial series mimicking the open 'milking' technique principle.

OBJECTIVE: To introduce a modified sequential vascular control strategy, mimicking the open 'milking' technique principle, for the early release of the first porta hepatis (FPH) and to stop cardiopulmonary bypass (CPB) in level III-IV robot-assisted inferior vena cava (IVC) thrombectomy (RA-IVCTE). PATIENTS AND METHODS: From November 2014 to June 2019, 27 patients with a level III-IV IVC tumour thrombus (IVCTT) underwent RA-IVCTE in our department. The modified sequential control strategy was used in 12 cases. Previously, we released the FPH after the thrombus was resected and the IVC was closed completely, and CPB was stopped at the end of surgery (15 patients). Presently, using our modified strategy, we place another tourniquet inferior to the second porta hepatis (SPH) once the proximal thrombus is removed from the IVC below the SPH. Then, we suture the right atrium and perform early release of the FPH, and stop CPB. Finally, tumour thrombectomy, vascular reconstruction, and radical nephrectomy are performed. RESULTS: Compared with the previous strategy, the modified steps resulted in a shorter median FPH clamping (19 vs 47 min, P < 0.001) and CPB times (60 vs 87 min, P < 0.05); a lower rate of Grade II-IV perioperative complications (25% vs 60%, P < 0.05); and better postoperative hepatorenal and coagulation function, including better median serum alanine aminotransferase (172.7 vs 465.4 U/L, P < 0.001), aspartate aminotransferase (282.4 vs 759.8 U/L, P < 0.001), creatinine (113.4 vs 295 µmol/L, P < 0.01), blood urea nitrogen (7.3 vs 16.7 mmol/L, P < 0.01), and D-dimer (5.9 vs 20 mg/L, P < 0.001) levels. CONCLUSION: With the early release of the FPH and stopping CPB, the modified sequential vascular control strategy in level III-IV RA-IVCTE reduced the perioperative risk for selected patients and improved the feasibility and safety of the surgery. We would recommend this approach to other centres that plan to develop robotic surgery for renal cell carcinoma with level III-IV IVCTT in the future.

Initial Series of Robotic Segmental Inferior Vena Cava Resection in Left Renal Cell Carcinoma With Caval Tumor Thrombus.

OBJECTIVE: To present our preliminary experience of robotic left radical nephrectomy (LRN) and segmental inferior vena cava (IVC) resection without caval replacement for left renal cell carcinoma (RCC) with inferior vena cava tumor thrombus. MATERIALS AND METHODS: Between 2017 and 2018, 7 patients underwent segmental IVC resection and LRN robotically. All patients underwent preoperative cavography, demonstrating complete IVC occlusion. Computed tomography-based 3-dimensional reconstruction revealed sufficient collateralization of the IVC and right renal vein (RRV). The cephalic IVC was circumferentially resected and ligated just below the second porta hepatis. The caudal IVC was circumferentially resected above the RRV with preservation of the major collaterals. The RRV was not dissected during the procedure to avoid compromising its neocollaterals. The IVC portion between the RRV and the second porta hepatis was removed en bloc with the tumor thrombus, and the LRN was performed. RESULTS: All cases were successfully performed by robotic surgery without conversion. Median operative time was 420 minutes. Median intensive care unit stay was 3 days. Four grade Ⅱ complications occurred in 2 patients. One patient had mild LEE postoperatively and recovered without special medication. Median preoperative and 3-6 months follow-up serum creatinine was 118.7 µmol/L and 135.2 µmol/L, respectively. No patient needed dialysis postoperatively. One case occurred disease progression. No patient died during the follow-up period. CONCLUSION: Robotic segmental IVC resection for left RCC with inferior vena cava tumor thrombus is feasible in well-selected cases. Three-dimensional reconstruction and cavography are helpful in the preoperative evaluation of neocollaterals in patients with suprarenal IVC occlusion.

Cumulative Sum Analysis of the Operator Learning Curve for Robot-Assisted Mayo Clinic Level I-IV Inferior Vena Cava Thrombectomy Associated with Renal Carcinoma: A Study of 120 Cases at a Single Center.

BACKGROUND This study aimed to use cumulative sum analysis of the operator learning curve for robot-assisted Mayo Clinic level I-IV inferior vena cava (IVC) thrombectomy associated with renal carcinoma, and describes the development of an optimized operative procedure at a single center. MATERIAL AND METHODS A retrospective study included 120 patients with Mayo Clinic level I-IV IVC thrombus who underwent robotic surgery between 2013 and 2018. Points in the learning curve were identified using cumulative sum analysis, and their impact was assessed by multiple regression analysis. Perioperative indicators analyzed included operative time, estimated blood loss, early complications, and the 90-day progression rate. RESULTS Cumulative sum analysis identified three phases in the learning curve of robot-assisted IVC thrombectomy. The median operative time decreased from 265 min (range, 212-401 min) to 207 min (range, 146-276 min) (p=0.003), the median estimated blood loss decreased from 775 ml (range, 413-1500 ml) to 300 ml (range, 163-813 ml) (p=0.006), and the early complication rate decreased from 52.5% to 15.0% (p<0.001). Multivariate analysis showed that for an initial 40 cases and a further 80 cases, the learning phase, the affected side, the Mayo Clinic level, and the surgical method were independent factors that affected operative time, estimated blood loss, and the rate of early complications. CONCLUSIONS Experience from an initial 40 cases and a further 80 cases of Mayo Clinic level I-IV IVC thrombectomy associated with renal carcinoma were found to provide acceptable surgical and clinical outcomes.

Comparison of Robot-Assisted and Laparoscopic Partial Nephrectomy for Completely Endophytic Renal Tumors: A High-Volume Center Experience.

Objectives: To compare the perioperative, functional, and oncologic outcomes of robot-assisted partial nephrectomy (RAPN) and laparoscopic partial nephrectomy (LPN) for completely endophytic renal tumors (three points for the "E" element of the R.E.N.A.L. scoring system). Materials and Methods: We retrospectively reviewed patients who underwent either RAPN or LPN between 2013 and 2016. Baseline characteristics, perioperative, functional, and oncologic outcomes were compared. Univariable and multivariable logistic analyses were performed to determine factors associated with pentafecta achievement (ischemia time ≤25 minutes, negative margin, no perioperative complication, return of estimated glomerular filtration rate [eGFR] to >90% from baseline, and no chronic kidney disease upstaging). Results: No significant differences between RAPN vs LPN were noted for operating time (105 minutes vs 108 minutes, p = 0.916), estimated blood loss (50 mL vs 50 mL, p = 0.130), renal artery clamping time (20 minutes vs 20 minutes, p = 0.695), rate of positive margins (3.3% vs 2.0%, p = 1.000), and postoperative complication rates (18.0% vs 21.6%, p = 0.639). RAPN was associated with a higher direct cost ($11240 vs $5053, p < 0.001). There were no significant differences in pathology variables, rate of eGFR decline for postoperative 12-month (9.8% vs 10.6%, p = 0.901) functional follow-up. Multivariate analysis identified that only RENAL score was independently associated with the pentafecta achievement. Conclusions: For completely endophytic renal tumors, both RAPN and LPN have excellent and similar results. Both operation techniques remain viable options in the management of these cases.

Promotion of Hyperthermic-Induced rDNA Hypercondensation in Saccharomyces cerevisiae.

Ribosome biogenesis is tightly regulated through stress-sensing pathways that impact genome stability, aging and senescence. In Saccharomyces cerevisiae, ribosomal RNAs are transcribed from rDNA located on the right arm of chromosome XII. Numerous studies reveal that rDNA decondenses into a puff-like structure during interphase, and condenses into a tight loop-like structure during mitosis. Intriguingly, a novel and additional mechanism of increased mitotic rDNA compaction (termed hypercondensation) was recently discovered that occurs in response to temperature stress (hyperthermic-induced) and is rapidly reversible. Here, we report that neither changes in condensin binding or release of DNA during mitosis, nor mutation of factors that regulate cohesin binding and release, appear to play a critical role in hyperthermic-induced rDNA hypercondensation. A candidate genetic approach revealed that deletion of either HSP82 or HSC82 (Hsp90 encoding heat shock paralogs) result in significantly reduced hyperthermic-induced rDNA hypercondensation. Intriguingly, Hsp inhibitors do not impact rDNA hypercondensation. In combination, these findings suggest that Hsp90 either stabilizes client proteins, which are sensitive to very transient thermic challenges, or directly promotes rDNA hypercondensation during preanaphase. Our findings further reveal that the high mobility group protein Hmo1 is a negative regulator of mitotic rDNA condensation, distinct from its role in promoting premature condensation of rDNA during interphase upon nutrient starvation.

Correction: Chl1 DNA helicase and Scc2 function in chromosome condensation through cohesin deposition.

[This corrects the article DOI: 10.1371/journal.pone.0188739.].

Radical Nephrectomy with or without Lymph Node Dissection for pT3 Renal Cell Carcinoma: A Propensity Score-based Analysis.

OBJECTIVES: To study whether radical nephrectomy (RN) with lymph node dissection (LND) can benefit pT3 renal cell carcinoma (RCC) patients versus no LND under the 2018 American Joint Committee on Cancer TNM classification system. Subjects/Patients and Methods: We performed a retrospective cohort study of clinicopathological data for 245 T3 RCC patients, who underwent radical nephrectomy between January 2006 and December 2013 at our center, including 67 (27.1%) who underwent LND. The relationships between the LND and progression-free survival (PFS), cancer-specific survival (CSS), and overall survival (OS) were evaluated using 1:1 propensity score (PS) matching. Then, Kaplan-Meier survival analysis and Cox regression analysis were conducted to study whether these patients can benefit from LND. Depending on the LND number, we divided the cohort into two groups for further comparation. At last, we validated the results with the TCGA database KIRC patients. RESULTS: The median follow-up time was 4.9 years. Sixty-seven pairs of patients were screened by the PS and were further analyzed. We conducted a Cox regression with the survival data and found that the LND group, compared with the non-LND group, showed no survival benefit on PFS, CSS, and OS (p = 0.444, 0.809, and 0.816, respectively). However, the removal of 5 or more LNs showed negative effect on OS (p = 0.0387). TCGA cohort results are mostly consistent with our findings. CONCLUSION: RN with LND cannot improve the PFS, CSS, or OS for pT3 renal cell carcinoma patients.

A Novel Preoperative Nomogram for Predicting Lymph Node Invasion in Renal Cell Carcinoma Patients Without Metastasis.

OBJECTIVE: To provide a preoperative predictive model to support clinical decision-making regarding the selection of in renal cell carcinoma (RCC) patients who will benefit the most from lymph node dissection. METHODS: This retrospective analysis enrolled 374 RCC patients without distant metastasis who underwent surgical treatment from January 2006 to December 2017. The relationships between lymph node invasion (LNI) and age at surgery; gender; body mass index(BMI); the presence of clinical symptoms such as flank pain, hematuria or a palpable mass; clinical T stage (cT stage); clinical N stage (cN stage); and the results of routine hematological and serum biochemical analyses were investigated. All the variables were included in univariate and multivariate logistic regression analyses, and the significant variables were then included in a novel nomogram to predict the probability of LNI. Then, we calibrated the nomogram with an internal validation set. RESULTS: Six of eighteen variables were significant in the univariate logistic regression analysis. After multivariate logistic regression analysis, age at surgery (OR=0.643, 95% CI: 0.421-0.975), cT stage (OR=3.034, 95% CI: 1.541-5.926), cN stage (OR=6.353, 95% CI: 3.273-12.456), lymphocyte percentage (OR=0.481, 95% CI: 0.256-0.894), and the presence of clinical symptoms (OR=2.045, 95% CI: 1.065-3.924) were independent predictors of LNI and were included in the nomogram. The C-index of this nomogram was 0.824. CONCLUSION: Preoperative basic laboratory findings combined with the results of a physical examination and radiological examination can indicate the probability of LNI in RCC patients.

Chl1 DNA helicase and Scc2 function in chromosome condensation through cohesin deposition.

Chl1 DNA helicase promotes sister chromatid cohesion and associates with both the cohesion establishment acetyltransferase Eco1/Ctf7 and the DNA polymerase processivity factor PCNA that supports Eco1/Ctf7 function. Mutation in CHL1 results in precocious sister chromatid separation and cell aneuploidy, defects that arise through reduced levels of chromatin-bound cohesins which normally tether together sister chromatids (trans tethering). Mutation of Chl1 family members (BACH1/BRIP/FANCJ and DDX11/ChlR1) also exhibit genotoxic sensitivities, consistent with a role for Chl1 in trans tethering which is required for efficient DNA repair. Chl1 promotes the recruitment of Scc2 to DNA which is required for cohesin deposition onto DNA. There is limited evidence, however, that Scc2 also directs the deposition onto DNA of condensins which promote tethering in cis (intramolecular DNA links). Here, we test the ability of Chl1 to promote cis tethering and the role of both Chl1 and Scc2 to promote condensin recruitment to DNA. The results reveal that chl1 mutant cells exhibit significant condensation defects both within the rDNA locus and genome-wide. Importantly, chl1 mutant cell condensation defects do not result from reduced chromatin binding of condensin, but instead through reduced chromatin binding of cohesin. We tested scc2-4 mutant cells and similarly found no evidence of reduced condensin recruitment to chromatin. Consistent with a role for Scc2 specifically in cohesin deposition, scc2-4 mutant cell condensation defects are irreversible. We thus term Chl1 a novel regulator of both chromatin condensation and sister chromatid cohesion through cohesin-based mechanisms. These results reveal an exciting interface between DNA structure and the highly conserved cohesin complex.

Temperature-dependent regulation of rDNA condensation in Saccharomyces cerevisiae.

Chromatin condensation during mitosis produces detangled and discrete DNA entities required for high fidelity sister chromatid segregation during mitosis and positions DNA away from the cleavage furrow during cytokinesis. Regional condensation during G1 also establishes a nuclear architecture through which gene transcription is regulated but remains plastic so that cells can respond to changes in nutrient levels, temperature and signaling molecules. To date, however, the potential impact of this plasticity on mitotic chromosome condensation remains unknown. Here, we report results obtained from a new condensation assay that wildtype budding yeast cells exhibit dramatic changes in rDNA conformation in response to temperature. rDNA hypercondenses in wildtype cells maintained at 37°C, compared with cells maintained at 23°C. This hypercondensation machinery can be activated during preanaphase but readily inactivated upon exposure to lower temperatures. Extended mitotic arrest at 23°C does not result in hypercondensation, negating a kinetic-based argument in which condensation that typically proceeds slowly is accelerated when cells are placed at 37°C. Neither elevated recombination nor reduced transcription appear to promote this hypercondensation. This heretofore undetected temperature-dependent hypercondensation pathway impacts current views of chromatin structure based on conditional mutant gene analyses and significantly extends our understanding of physiologic changes in chromatin architecture in response to hypothermia.