p21-activated kinase 1 predicts recurrence and survival in patients with non-metastatic clear cell renal cell carcinoma

Review of Prognostic Expression Markers for Clear Cell Renal Cell Carcinoma

Context: The number of prognostic markers for clear cell renal cell carcinoma (ccRCC) has been increasing regularly over the last 15 years, without being integrated and compared.

Objective: Our goal was to perform a review of prognostic markers for ccRCC to lay the ground for their use in the clinics.

Evidence Acquisition: PubMed database was searched to identify RNA and protein markers whose expression level was reported as associated with survival of ccRCC patients. Relevant studies were selected through cross-reading by two readers.

Evidence Synthesis: We selected 249 studies reporting an association with prognostic of either single markers or multiple-marker models. Altogether, these studies were based on a total of 341 distinct markers and 13 multiple-marker models. Twenty percent of these markers were involved in four biological pathways altered in ccRCC: cell cycle, angiogenesis, hypoxia, and immune response. The main genes (VHL, PBRM1, BAP1, and SETD2) involved in ccRCC carcinogenesis are not the most relevant for assessing survival.

Conclusion: Among single markers, the most validated markers were KI67, BIRC5, TP53, CXCR4, and CA9. Of the multiple-marker models, the most famous model, ClearCode34, has been highly validated on several independent datasets, but its clinical utility has not yet been investigated.

Patient Summary: Over the years, the prognosis studies have evolved from single markers to multiple-marker models. Our review highlights the highly validated prognostic markers and multiple-marker models and discusses their clinical utility for better therapeutic care.

PAK1 as a Potential Therapeutic Target in Male Smokers with EGFR-Mutant Non-Small Cell Lung Cancer

P21-activated kinases (PAKs) are serine/threonine protein kinases that contribute to several cellular processes. Here, we aimed to determine the prognostic value of PAK1 and its correlation with the clinicopathological characteristics and five-year survival rates in patients with non-small cell lung cancer (NSCLC). We evaluated PAK1 mRNA and protein expression in NSCLC cells and resected tumor specimens, as well as in healthy human bronchial epithelial cells and adjacent healthy lung tissues, respectively, for effective comparison. Immunohistochemical tissue microarray analysis of 201 NSCLC specimens showed the correlation of PAK1 expression with clinicopathological characteristics. The mRNA and protein expression of PAK1 were 2.9- and 4.3-fold higher in six of seven NSCLC cell types and human tumors (both, p < 0.001) than in healthy human bronchial epithelial BEAS-2B cells and adjacent healthy lung tissues, respectively. Decreased survival was significantly associated with PAK1 overexpression in the entire cohort (χ² = 8.48, p = 0.0036), men (χ² = 17.1, p < 0.0001), and current and former smokers (χ² = 19.2, p < 0.0001). Notably, epidermal growth factor receptor (EGFR) mutation-positive lung cancer patients with high PAK1 expression showed higher mortality rates than those with low PAK1 expression (91.3% vs. 62.5%, p = 0.02). Therefore, PAK1 overexpression could serve as a molecular target for the treatment of EGFR mutation-positive lung cancer, especially among male patients and current/former smokers.

PAK1 expression determines poor prognosis and immune evasion in metastatic renal cell carcinoma patients

BACKGROUND

Previous studies have shown the prognostic value of PAK1 expression in different tumor patients, including nonmetastatic renal cell carcinoma. In this study, we explored the prognostic and drug predictive value of PAK1 expression in metastatic renal cell carcinoma (mRCC) patients treated with tyrosine kinase inhibitors (TKIs).

MATERIALS AND METHODS

We retrospectively enrolled 138 mRCC patients treated with TKIs from a single institution from 2005 to 2014. Analyses were based on 111 patients who met our inclusion criteria. The validation set enrolled 538 RCC patients from The Cancer Genome Atlas Kidney Renal Clear Cell Carcinoma cohort (TCGA KIRC) between 1998 and 2013 in North America. PAK1 expression was assessed by immunohistochemistry (IHC) on tissue microarrays.

RESULTS

High PAK1 expression was associated with short overall survival (OS) (P < 0.001) and progression-free survival (PFS) (P = 0.008). Multivariate analyses further indicated that PAK1 expression was an independent prognostic factor for OS (hazard ratio 3.301 [95% confidence interval 2.579-10.899], P < 0.001) and PFS (hazard ratio 3.108 [95% confidence interval 1.795-5.381], P < 0.001). Subgroup analyses suggested that PAK1 was more significant in patients with the intermediate risk group of Heng risk criteria (OS, P = 0.004). Of note, patients treated with Sunitinib showed improved outcome in the low PAK1 subgroup (OS, P = 0.002; PFS, P = 0.013). Finally, relationship was found between PAK1 expression and natural killer cell-mediated cytotoxicity according to gene profile investigation.

CONCLUSIONS

High PAK1 expression predicted dismal prognosis in mRCC patients treated with TKIs. Besides, PAK1 was a potential predictor for TKIs treatments.

Tumor necrosis as a prognostic variable for the clinical outcome in patients with renal cell carcinoma: a systematic review and meta-analysis

Background

Tumor necrosis (TN) correlates with adverse outcomes in numerous solid tumors. However, its prognostic value in renal cell carcinoma (RCC) remains unclear. In this study, we performed a meta-analysis to evaluate associations between TN and cancer-specific survival (CSS), overall survival (OS), recurrence-free survival (RFS) and progression-free-survival (PFS) in RCC.

Methods

Electronic searches in PubMed, EMBASE and Web of Science were conducted according to the PRISMA statement. Hazard ratios (HRs) and 95% confidence intervals (95% CIs) were calculated to evaluate relationships between TN and RCC. A fixed- or random-effects model was used to calculate pooled HRs and 95%CIs according to heterogeneity.

Results

A total of 34 cohort studies met the eligibility criteria of this meta-analysis. The results showed that TN was significantly predictive of poorer CSS (HR = 1.37, 95% CI: 1.23–1.53, p < 0.001), OS (HR = 1.29, 95% CI: 1.20–1.40, p < 0.001), RFS (HR = 1.55, 95% CI: 1.39–1.72, p < 0.001) and PFS (HR = 1.31, 95% CI: 1.17–1.46, p < 0.001) in patients with RCC. All the findings were robust when stratified by geographical region, pathological type, staging system, number of patients, and median follow-up.

Conclusions

The present study suggests that TN is associated with CSS, OS, RFS and PFS clinical outcomes of RCC patients and may serve as a predictor of poor prognosis in these patients.

Electronic supplementary material

The online version of this article (10.1186/s12885-018-4773-z) contains supplementary material, which is available to authorized users.

Overexpression of PAK1 Correlates with Aberrant Expression of EMT Markers and Poor Prognosis in Non-Small Cell Lung Cancer

Objective: p21-activated kinases (PAKs) are serine/threonine protein kinases. PAK1 and epithelial-mesenchymal transition (EMT) are key therapeutic targets in cancer. The clinical significance of PAK1 and its potential association with EMT phenotype in non-small cell lung cancer (NSCLC) was investigated. Methods: Immunohistochemistry was used to detect the expression of PAK1, and mesenchymal and epithelial markers (vimentin, N-cadherin, and E-cadherin) in 186 cases of NSCLC tissues and 50 cases of tumor-adjacent normal tissues. The correlation of PAK1 with the clinicopathological characteristics, prognosis, and mesenchymal and epithelial markers in NSCLC were analyzed. Results: Compared with the non-tumor tissues, PAK1, vimentin, and N-cadherin levels were markedly elevated in NSCLC tissues, whereas the E-cadherin levels were significantly decreased (P<0.05). The aberrant expression of PAK1 was significantly associated with TNM stage and metastasis (P<0.001). Patients who displayed high expression of PAK1 may achieve a poorer progression-free survival (PFS) and overall survival (OS), compared to those with low expression of PAK1 (P=0.001 and P<0.001). Univariate and multivariate analysis showed that high expression of PAK1 was an independent predictor of poor prognosis [hazard ratio (HR) =2.121, P<0.001, HR=1.928, P=0.001, respectively]. In addition, significant correlations were observed between the EMT markers and OS or PFS (P<0.01). Interestingly, PAK1 expression was positively correlated with vimentin and N-cadherin levels (r=0.473, P<0.001; r=0.526, P<0.001, respectively) and negatively correlated with E-cadherin levels (r=-0.463, P<0.001) in NSCLC tissues. Conclusion: PAK1 may promote NSCLC progression and metastasis through EMT, thereby exhibiting the potential of an efficient prognostic predictor in NSCLC patients.