LncRNA HIF1A-AS2 accelerates malignant phenotypes of renal carcinoma by modulating miR-30a-5p/SOX4 axis as a ceRNA

OBJECTIVE

Several reports have proposed that lncRNAs, as potential biomarkers, participate in the progression and growth of malignant tumors. HIF1A-AS2 is a novel lncRNA and potential biomarker, involved in the genesis and development of carcinomas. However, the molecular mechanism of HIF1A-AS2 in renal carcinoma is unclear.

METHODS

The relative expression levels of HIF1A-AS2 and miR-30a-5p were detected using RT-qPCR in renal carcinoma tissues and cell lines. Using loss-of-function and overexpression, the biological effects of HIF1A-AS2 and miR-30a-5p in kidney carcinoma progression were characterized. Dual luciferase reporter gene analysis and Western blot were used to detect the potential mechanism of HIF1A-AS2 in renal carcinomas.

RESULTS

HIF1A-AS2 was upregulated in kidney carcinoma tissues when compared with para-carcinoma tissues (P < 0.05). In addition, tumor size, tumor node mestastasis stage and differentiation were identified as being closely associated with HIF1A-AS2 expression (P < 0.05). Knockdown or overexpression of HIF1A-AS2 either restrained or promoted the malignant phenotype and WNT/β-catenin signaling in renal carcinoma cells (P < 0.05). MiR-30a-5p was downregulated in renal cancers and partially reversed HIF1A-AS2 functions in malignant renal tumor cells. HIF1A-AS2 acted as a microRNA sponge that actively regulated the relative expression of SOX4 in sponging miR-30a-5p and subsequently increased the malignant phenotypes of renal carcinomas. HIF1A-AS2 showed a carcinogenic effect and miR-30a-5p acted as an antagonist of the anti-oncogene effects in the pathogenesis of renal carcinomas.

CONCLUSIONS

The HIF1A-AS2-miR-30a-5p-SOX4 axis was associated with the malignant progression and development of renal carcinoma. The relative expression of HIF1A-AS2 was negatively correlated with the expression of miR-30a-5p, and was closely correlated with SOX4 mRNA levels in renal cancers.

The critical impact of tumor size in predicting cancer special survival for T3aM0M0 renal cell carcinoma: A proposal of an alternative T3aN0M0 stage

OBJECTIVE

Based on the eighth TNM staging system, T3a renal cell carcinoma (RCC) is identified as an anatomical extrarenal invasion and does not consider the size of the tumor; however, it may not fully predict the prognosis of the patient. The objective of this study was to evaluate the prognostic value of tumor size effects on prognosis in T3a RCC and propose an alternative tumor stage system combined with T1-2.

METHODS

Data relating to T1-3aN0M0 RCC (n = 49586) were obtained from the Surveillance, Epidemiology, and End Results database (2004-2015). Survival analyses were conducted by Cox regression and Fine and Gray regression. Harrell's concordance index (c-index) was used to assess the discriminatory ability of the prognostic factors.

RESULTS

A 1-cm increase in T3a RCC resulted in an 8% increase in all-cause mortality (hazard ratio [HR]: 1.08; 95% confidence interval [CI]: 1.06-1.10, p < 0.001) and 14% increase in the risk of RCC-specific mortality (sub-distribution HR [sHR]: 1.14; 95% CI: 1.11-1.16, p < 0.001). T3a tumor size stratified by the cutoff of 4 cm and 7 cm showed a better prediction of RCC-special survival (c-index: 0.644), compared with a cutoff just by 4 cm (c-index: 0.571) or by 7 cm (c-index: 0.602). Compared with T1b tumors, T3a RCC ≤4 cm showed no differences in terms of all-cause mortality (HR: 0.93; 95% CI: 0.79-1.09; p = 0.37) and mortality caused by RCC (sHR: 0.91; 95% CI: 0.70-1.19; p = 0.50). Last, the alternative T-staging system (T1a, a combination of T1b and T3a [≤4 cm], T2a, T2b, T3a [4-7 cm], and T3a [>7] cm) demonstrated good RCC-special survival predictive accuracy (c-index: 0.729), which was higher than that shown by the current eighth edition T-staging system (c-index: 0.720).

CONCLUSION

Tumor size should be taken into consideration for T3aN0M0 RCC rather than based on anatomical features alone.

The diagnostic value of multi-slice spiral computed tomography in patients with renal carcinoma

Objective

This study was aimed to investigate the characteristics of multi-slice spiral computed tomography (CT) image in kidney cancer patients and its clinical value in staging diagnosis of kidney cancer.

Materials and Methods

This study included 57 patients who were confirmed as kidney cancer through postoperative pathological examination; they were diagnosed within February 2014 and December 2016 in our hospital. The data obtained from multi-slice spiral CT plain scan and contrast-enhanced CT of these patients was retrospectively analyzed. Moreover, we determined the characteristics of multi-slice spiral CT image for kidney cancer and analyzed their consistency with pathological staging.

Results

CT plain scan showed that kidney lumps were mostly found in the prominent renal contour or renal parenchyma, and they were round-like or round in shape. Among the 57 included patients, the tumors of 43 cases showed regular edges, and 14 showed irregular edges. Among the 14 cases, 10 patients had tumors with lobulated edges and 5 with spinous tumor edge. Among all the 57 patients, CT plain scan showed there were 5 cases with slightly higher density, 24 cases with mixed density, 28 cases with equal density or slightly lower density. The range of tumor diameter was 2.1-12.6 cm; the tumor diameter was smaller than 3 cm in 11 cases, 3-7 cm in 34 cases, and larger than 7 cm in 12 cases. In terms of contrast enhancement, the arterial phase was obviously enhanced in 31 cases, moderately and irregularly enhanced in 18 cases, and slightly enhanced in 8 cases. Moreover, the renal parenchymal scan showed a rapid decline in the enhancement and a further decline in the enhancement of renal pelvic tumor; the three stages of enhancement could be expressed in terms of fast forwardness and fast backwardness. A total of 33, 4, 9, and 11 cases were classified as postoperative pathological Stage I, II, III, and IV, respectively; 35, 5, 7, and 10 cases were classified as CT scan Stage I, II, III, and IV, respectively; and 34, 5, 8, and 10 cases were classified as contrast-enhanced CT scan Stage I, II, III, and IV, respectively. No significant difference was observed in the frequency of CT scan, the enhanced stage and pathological stage (P > 0.05).

Conclusion

CT image of kidney cancer revealed the morphological and enhanced features of this tumor. The consistency between CT stage and pathological stage was high; thus, this method can be applied as a forecasting method for pathological staging.

UBASH3B-mediated silencing of the mitotic checkpoint: Therapeutic perspectives in cancer

Defects in mitosis can lead to aneuploidy, which is a common feature of human cancers. Spindle Assembly Checkpoint (SAC) controls fidelity of chromosome segregation in mitosis to prevent aneuploidy. The ubiquitin receptor protein Ubiquitin Associated and SH3 Domain Containing B (UBASH3B) was recently found to control SAC silencing and faithful chromosome segregation by relocalizing Aurora B kinase to the mitotic microtubules. Accordingly, loss and gain of function of UBASH3B have strong effects on mitotic progression. Downregulation of UBASH3B prevents SAC satisfaction leading to inhibition of chromosome segregation, mitotic arrest, and cell death. In contrast, increased cellular levels of UBASH3B trigger premature and uncontrolled chromosome segregation. Interestingly, elevated levels of UBASH3B were found in aggressive tumors. Therefore, we raised the question whether the oncogenic potential of UBASH3B is linked to its role in chromosome segregation. Here we show that in cancer cells expressing high levels of UBASH3B and SAC proteins, downregulation of UBASH3B, can further potentiate SAC response inducing mitotic arrest and cell death. Moreover, data mining approaches identified a correlation between mRNA levels of UBASH3B and SAC components in a set of primary patient tumors including kidney and liver carcinomas. Thus, inhibition of UBASH3B may offer an attractive therapeutic perspective for cancers.

Toxicity of Checkpoint Inhibition in Advanced RCC: A Systematic Review

Background:

Checkpoint inhibitors (CPI) have now been established as standard agents in the management of patients with metastatic renal cell carcinoma (mRCC). Given the unique toxicity profiles of CPIs, a detailed understanding of their incidence rate and characteristics is critical.

Objective:

To perform a systematic review for the analysis of the incidence rate and characteristics of toxicities in mRCC patients treated with CPIs in published clinical trials.

Methods:

A systematic search of EMBASE (Ovid) and MEDLINE (Ovid) was conducted as per PRISMA guidelines to identify prospective clinical trials of checkpoint inhibitors in mRCC. The search method involved querying for the terms renal cell carcinoma or kidney carcinoma with any of the following: programmed cell death 1, PD-1, programmed cell death ligand 1, PD-L1, cytotoxic T-lymphocyte antigen 4, CTLA-4, immunotherapy, checkpoint inhibitor, anti-PD-1, or anti-PD-L1. Only prospective clinical trials were included.

Results:

The systematic review yielded 9,722 records through the MEDLINE (Ovid) and EMBASE (Ovid) databases. Ultimately, five prospective clinical trials with 722 patients were selected for inclusion. The rates of any grade adverse event (AE) and grade (G) 3-4 AEs were 79.9% and 20.9%, respectively. Regarding immune-related AEs (irAEs), the most common system affected by any grade irAE was the skin (30.89%) and the most common grade 3-4 irAE was related to the hepatic system (8.23%). Rates of AEs were similar across the CPI monotherapy clinical trials.

Conclusions:

The rates of AEs in mRCC patients treated with CPI is similar to rates in other cancers. AEs in mRCC are fairly consistent among monotherapy trials with PD-1 and PD-L1 inhibitors and as one would expect higher when CTLA-4 and PD-1 inhibitors are offered in combination.

New HIF2α inhibitors: potential implications as therapeutics for advanced pheochromocytomas and paragangliomas

Two recent independent studies published in Nature show robust responses of clear cell renal cell carcinoma (ccRCC) cell lines, preclinical ccRCC xenograft models and, remarkably, a patient with progressive ccRCC despite receiving multiple lines of treatment, to the long-awaited, recently developed inhibitors of hypoxia-inducible factor 2-alpha (HIF2α). This commentary published in Endocrine-Related Cancer is based on the recognition of similar molecular drivers in ccRCC and the endocrine neoplasias pheochromocytomas and paragangliomas (PPGLs), ultimately leading to stabilization of HIFs. HIF-stabilizing mutations have been detected in the von Hippel-Lindau (VHL) gene, as well as in other genes, such as succinate dehydrogenase (SDHx), fumarate hydratase (FH) and transcription elongation factor B subunit 1 (TCEB1), as well as the gene that encodes HIF2α itself: EPAS1^HIF2α Importantly, the recent discovery of EPAS1 mutations in PPGLs and the results of comprehensive in vitro and in vivo studies revealing their oncogenic roles characterized a hitherto unknown direct mechanism of HIF2α activation in human cancer. The now available therapeutic opportunity to successfully inhibit HIF2α pharmacologically with PT2385 and PT2399 will certainly spearhead a series of investigations in several types of cancers, including patients with SDHB-related metastatic PPGL for whom limited therapeutic options are currently available. Future studies will determine the efficacy of these promising drugs against the hotspot EPAS1 mutations affecting HIF2α amino acids 529-532 (in PPGLs) and amino acids 533-540 (in erythrocytosis type 4), as well as against HIF2α protein activated by VHL, SDHx and FH mutations in PPGL-derived chromatin cells.

Inhibition of PKCα reduces the ability of migration of kidney cancer cells but has no impact on cell apoptosis

Kidney cancer is among the most important causes of cancer-associated mortality worldwide. The present study aimed to evaluate protein kinase C α (PKCα) expression in kidney cancer tissues and cell lines, and its significance in apoptosis and migration. Expression of PKCα was analyzed using quantitative polymerase chain reaction and western blotting. In addition, the inhibitor of PKCα (calphostin C and GO6976) was used to treat kidney cancer cells. The ACHN cell line was generated with PKCα-small-interfering RNA (siRNA) and a stable expression of PKCα, in order to facilitate the analysis of apoptosis and migration of PKCα during knockdown and inactivation. Flow cytometry was used to determine the rates of apoptosis. Immunohistochemical staining was used to identify the localization of PKCα in renal clear cell carcinoma and normal sections. PKCα expression in normal tissues was found to be greater than in cancerous tissues. Furthermore, apoptosis was not promoted with PKCα inhibitors or PKCα-siRNA treatment, and a decrease of the migration ability was observed following transfection with PKCα-dominant negative. The results indicated that inhibition of PKCα might not contribute to apoptosis progression in kidney carcinoma.

Identification of underserved areas for urologic cancer care

BACKGROUND

The delivery of urologic oncology care is susceptible to regional variation. In the current study, the authors sought to define patterns of care for patients undergoing genitourinary cancer surgery to identify underserved areas for urologic cancer care in Washington State.

METHODS

The authors accessed the Washington State Comprehensive Hospital Abstract Reporting System from 2003 through 2007. They identified patients undergoing radical prostatectomy, radical cystectomy (RC), partial nephrectomy (PN), radical nephrectomy, and transurethral resection of the prostate (TURP). TURP was included for comparison as a reference procedure indicative of access to urologic care. Hospital service areas (HSAs) are where the majority of local patients are hospitalized; hospital referral regions (HRR) are where most patients receive tertiary care. The authors created multivariate hierarchical logistic regression models to examine patient and HSA characteristics associated with the receipt of urologic oncology care out of the HRR for each procedure.

RESULTS

Greater than one-half of patients went out of their HRR in 7 HSAs (11%) for radical prostatectomy, 3 HSAs (5%) for radical nephrectomy, 10 HSAs (15%) for PN, and 14 HSAs (22%) for RC. No HSAs had high export rates for TURP. Few patient factors were found to be associated with surgical care out of the HRR. High-export HSAs for PN and RC exhibited lower socioeconomic characteristics than low-export HSAs, adjusting for HSA population, race, and HSA procedure rates for PN and RC.

CONCLUSIONS

Patients living in areas with lower socioeconomic status have a greater need to travel for complex urologic surgery. Consideration of geographic delineation in the delivery of urologic oncology care may aid in regional quality improvement initiatives.

Matrix metalloproteinase-2 and -9 and tissue inhibitor of metalloproteinase-1 and -2 in sera and urine of patients with renal carcinoma

The matrix metalloproteinase (MMP) family has been shown to play a critical role in tissue remodeling and tumor infiltration. Their activity is normally strictly controlled by tissue inhibitors of metalloproteinases (TIMPs). However, TIMPs act indirectly through modulation of protease activity or directly through cell surface receptors to direct cell fate. These molecules have been proposed as markers of malignant cancer. Previous studies on MMP and TIMP expression in kidney carcinoma have been limited and have reported variable observations. The current study measured the content of MMP-2 and -9 and TIMP-1 and -2 in the sera and urine of patients with kidney carcinoma by enzyme-linked immunosorbent assay. Of these patients, 16 exhibited clear cell renal cell carcinoma (ccRCC) and 4 exhibited oncocytoma. Sera and urine samples of 53 healthy subjects were used as controls. In the sera of the control group, MMP-2 and TIMP-2 were detectable in all samples, while MMP-9 and TIMP-1 were below the sensitivity of the assay. In the pathological specimens, the mean serum values of MMP-2 and TIMP-1 and -2 were similar in the ccRCC and oncocytoma patients, whereas the value for MMP-9 was 2-fold higher in the ccRCC patients compared with the oncocytoma patients. With regard to the urine specimens, all four molecules were undetectable in the normal healthy samples and in a few pathological samples. The mean values for MMP-2 and -9 and TIMP-2 in the positive urine specimens were similar in the ccRCC and oncocytoma patients, whereas the mean value of TIMP-1 was higher in the ccRCC patients compared with that of the oncocytoma patients. The mean urinary levels of the four molecules were less than those of the sera. Statistical analysis of the data did not reveal any correlation between the tumor grades and expression levels of the molecules examined.