Genetic mutations associated with metastatic clear cell renal cell carcinoma

The prognostic values and immune characteristics of polo-like kinases (PLKs) family: A pan-cancer multi-omics analysis

Background

In the realm of tumor-targeted therapeutics, Polo-like kinases (PLKs) are a significant group of protein kinases that were found recently as being related to tumors. However, the significance of PLKs in pan-cancer remains systematically studied.

Methods and materials

We integrated multi-omics data to comprehensively investigate the expression patterns of the PLK family across various cancer types. Subsequently, study examined the associations between tumor mutation burden (TMB), microsatellite instability (MSI), immune subtype classification, immune infiltration, tumor microenvironment scores, immune checkpoint gene expression, and the PLKs expression profiles within various tumor types. Furthermore, using our mRNA sequencing data (TRUCE01) and four bladder cancer (BLCA) cohorts (GSE111636, GSE176307, and IMvigor210), We examined the correlation between the expression level of PLK and immunotherapy effectiveness. Next, Gene set enrichment analysis (GSEA) was evaluated to find that potentially enriched PLK signaling pathways. Utilizing TIMER 2.0, we conducted an immune infiltration analysis underlying transcriptome expression, copy number variations (CNV), or somatic mutations of PLKs in BLCA. Finally, mRNA expression validation of PLK1/3/4 by real-time PCR within 10 paired BLCA tissues, protein expression verification through the Human Protein Atlas (HPA), and PLK4 in vitro cytological studies have been employed in BLCA.

Results

The expression of most of the PLK family members exhibits variation between cancerous tissues and adjacent normal tissues across various cancer species. Furthermore, the expression of PLKs demonstrates a significant association with immunotyping, infiltration of immune cell, tumor mutational burden (TMB), microsatellite instability (MSI), immunological checkpoint gene activity and therapeutic effectiveness in pan-tumor tissues. Additional investigation into the correlation between the PLK family and BLCA has revealed that the expression of the PLK genes holds substantial significance in the biological processes of BLCA. Furthermore, a notable association has been observed between the copy number variation, variant status, and the degree of certain immunological cell infiltration. Of note, the expression validation and in vitro phenotypic experiments have demonstrated that PLK4 has a significant function in promoting the BLCA cell proliferation, migration, and invasion.

Conclusion

Collectively, based on various databases, our results highlight the involvement of PLK gene family in the formation of different types of tumors and identify PLK-related genes that may be used for therapy.

Potential Tumor Suppressor Role of Polo-like Kinase 5 in Cancer

The polo-like kinase (PLK) family of serine/threonine kinases contains five members (PLK1-5). Most PLKs are involved in cell cycle regulation and DNA damage response. However, PLK5 is different as it lacks a functional kinase domain and is not involved in cell cycle control. PLK5 remains the least-studied family member, and its role in oncogenesis remains enigmatic. Here, we identified tissues with high PLK5 expression by leveraging the Protein Atlas and GTEx databases with relevant literature and selected ovarian, lung, testis, endometrium, cervix, and fallopian tube tissues as candidates for further investigation. Subsequently, we performed immunohistochemical staining for PLK5 on multiple tissue microarrays followed by Vectra scanning and quantitative inForm analysis. This revealed consistently downregulated PLK5 expression in these cancers compared to normal tissues. To validate and extend our findings, we performed pan-cancer analysis of PLK5 expression using public RNAseq databases (TCGA and GTEx). We found PLK5 is downregulated in 18 cancer types, including our selected candidates. Interestingly, we also observed PLK5 expression remains consistently low in later stages of cancer, suggesting PLK5 may have a greater role in tumor initiation than cancer progression. Overall, our study demonstrates PLK5 downregulation in multiple cancers, highlighting its role as a tumor suppressor.

Polo-like kinase (PLK) 5, a new member of the PLK family, serves as a biomarker to indicate anabatic tumor burden and poor prognosis for resectable non-small cell lung cancer

Objective

A review argues that polo-like kinase 5 (PLK5) may be linked to unfavorable prognosis in non-small cell lung cancer (NSCLC) patients, which contradicts the discoveries from The Human Protein Atlas database (derived from TCGA analysis). This study intended to comprehensively confirm the association of PLK5 with clinical characteristics and prognosis in NSCLC patients.

Methods

This two-center, retrospective, cohort study enrolled 210 NSCLC patients receiving surgical resection. PLK5 protein and mRNA were detected by immunohistochemistry and RT-qPCR in tumor and nontumor tissues. Moreover, RNA FPKM data for 994 lung cancer patients were obtained from The Human Protein Atlas database.

Results

PLK5 protein was decreased in tumor tissue compared to nontumor tissue (P < 0.001). Additionally, decreased PLK5 protein was linked with increased pathological grade (P = 0.002), lymph node metastasis presence (P = 0.001), elevated tumor-node-metastasis (TNM) stage (P = 0.003), and abnormal cancer antigen 125 (CA125) (P = 0.002). Meanwhile, low PLK5 protein was correlated with shortened disease-free survival (DFS) (P = 0.007) and overall survival (OS) (P = 0.038); further multivariable Cox regression analysis revealed that low PLK5 protein independently predicted unfavorable DFS (hazard ratio = 0.573, P = 0.022). PLK5 mRNA was reduced in tumor tissue compared with nontumor tissue (P < 0.001); its decline was linked with enhanced pathological grade (P = 0.034), climbed TNM stage (P = 0.032), and abnormal CA125 (P = 0.002). Furthermore, low PLK5 mRNA was correlated with unfavorable DFS (P = 0.046). The Human Protein Atlas database also disclosed the link between low PLK5 mRNA and worse OS (P = 0.046).

Conclusion

A PLK5 decrement reflects anabatic tumor burden and poor prognosis in NSCLC patients.

Comprehensive analysis of PLKs expression and prognosis in breast cancer

OBJECTIVE

A thorough examination of PLKs in breast cancer, including their expression and prognosis.

METHODS

With the help of the Oncomine database, the transcript levels of PLKs in breast cancer were examined. The changes in PLKs expression with tumor stage and indeed the relationship between PLKs expression and stage of cancer in women with breast cancer were scrutinized by using the GEPIA database. Based on Kaplan-Meier plots, breast cancer patients were assessed for their prognosis. Breast cancer gene expression and mutations were analyzed within the cBioPortal database.

RESULTS

According to Oncomine data, PLK1 and PLK4 mRNA expression levels were dramatically elevated in breast cancer patients while PLK2 and PLK5P levels were significantly downregulated. PLK1 and PLK4 expression were discovered to be greater in breast cancer tissues than in healthy tissues following analysis of the GEPIA database (P < 0.05). High levels of PLK1 and PLK4 transcripts have been linked to poor relapse-free survival rates across all patients with breast cancer according to the Kaplan-Meier Plotter database. The high levels of PLK2, PLK3, and PLK5 were associated with a higher recurrence-free survival rate. In the cBioPortal database, PLK was altered in 9.6% of breast cancer samples. Genetic alterations occurred in 15.07% of clinically counted invasive breast cancers, with mutations in 4.11%, gene amplifications in 9.59%, and gene deletion mutations in 1.37%. Additionally, the KEGG database demonstrates that PLKs are crucial for the cell cycle. The findings imply that elevated PLK1 and PLK4 expression in tissues of breast cancer might contribute significantly to the carcinogenesis of breast cancer. Moreover, PLK1 and PLK4 are highly expressed in breast cancer, and their use as molecular markers to identify high-risk subsets from patients with breast cancer is potentially possible.

CONCLUSIONS

For the precise therapy of breast cancers, PLK1 and PLK4 are potential targets, while PLK2, PLK3, and PLK5 are brand-new biomarkers for predicting the prognosis of breast cancer.

KLF2-induced circZKSCAN1 potentiates the tumorigenic properties of clear cell renal cell carcinoma by targeting the miR-1294/PIM1 axis

Clear cell renal cell carcinoma (ccRCC) is one of the most common and lethal types of urologic cancer. With low survival rates among patients in advanced stages of disease, and increasing rate of morbidity and mortality worldwide, novel therapeutic targets for ccRCC clinical intervention are necessary. In this study, we investigated the functional role of circZKSCAN1 in ccRCC progression. Our results suggested that circZKSCAN1 was abundantly expressed in ccRCC tumor tissues and cells. CircZKSCAN1 knockdown significantly inhibited cell proliferation, migration, invasion, and epithelial-to-mesenchymal transition of renal cell carcinoma (RCC) cells, whereas potentiated Natural Killer (NK) cell-mediated cytotoxicity against RCC cells in vitro and repressed tumor growth in vivo. Furthermore, we identified a novel circZKSCAN1/miR-1294/PIM1 axis was identified in RCC progression, showing that the expression of circZKSCAN1 expression in RCC cells was transcriptionally regulated by Kruppel-like factor 2. The results of our study may provide new insights for ccRCC basic research.Abbreviations: ccRCC: clear cell renal cell carcinoma; ChIP: chromatin immunoprecipitation; circRNA: circular RNA; EDU: 5-ethynyl-2'-deoxyuridine; EMT: epithelial-mesenchymal transition; FBS: fetal bovine serum; FISH: RNA fluorescent in situ hybridization; KLF2: Kruppel-like factor 2; NC: normal control; NK cell: natural killer cell; NOD/SCID: nonobese severe diabetic/severe combined immunodeficiency; PIM1: Pim-1 proto-oncogene, serine/threonine kinase; RCC: renal cell carcinoma; ZKSCAN1: zinc finger with KRAB and SCAN domains 1.

Modelling the Functions of Polo-Like Kinases in Mice and Their Applications as Cancer Targets with a Special Focus on Ovarian Cancer

Polo-like kinases (PLKs) belong to a five-membered family of highly conserved serine/threonine kinases (PLK1-5) that play differentiated and essential roles as key mitotic kinases and cell cycle regulators and with this in proliferation and cellular growth. Besides, evidence is accumulating for complex and vital non-mitotic functions of PLKs. Dysregulation of PLKs is widely associated with tumorigenesis and by this, PLKs have gained increasing significance as attractive targets in cancer with diagnostic, prognostic and therapeutic potential. PLK1 has proved to have strong clinical relevance as it was found to be over-expressed in different cancer types and linked to poor patient prognosis. Targeting the diverse functions of PLKs (tumor suppressor, oncogenic) are currently at the center of numerous investigations in particular with the inhibition of PLK1 and PLK4, respectively in multiple cancer trials. Functions of PLKs and the effects of their inhibition have been extensively studied in cancer cell culture models but information is rare on how these drugs affect benign tissues and organs. As a step further towards clinical application as cancer targets, mouse models therefore play a central role. Modelling PLK function in animal models, e.g., by gene disruption or by treatment with small molecule PLK inhibitors offers promising possibilities to unveil the biological significance of PLKs in cancer maintenance and progression and give important information on PLKs' applicability as cancer targets. In this review we aim at summarizing the approaches of modelling PLK function in mice so far with a special glimpse on the significance of PLKs in ovarian cancer and of orthotopic cancer models used in this fatal malignancy.

Ubiquitin-specific peptidase 53 inhibits the occurrence and development of clear cell renal cell carcinoma through NF-κB pathway inactivation

Background

Clear cell renal cell carcinoma (ccRCC) is one of the most prevalent malignant diseases in the urinary system with more than 140,000 related deaths annually. Ubiquitination–deubiquitination homeostasis is an important factor in ccRCC progression; ubiquitin‐specific peptidase 53 (USP53) belongs to the family of deubiquitinating enzymes, but its functions are rarely reported.

Methods

Databases obtained from GEO and TCGA were analyzed to reveal the role of USP53 in ccRCC. CCK‐8/BrdU and EDU assays were used to detect the proliferation of ccRCC after USP53 overexpression or knockdown. A tumor xenograft experiment was used to verify the effect of the proliferation of ccRCC after USP53 knockdown. Transwell assays were used to detect the metastasis of ccRCC after USP53 overexpression or knockdown. RNA sequencing and western blot analysis were employed to detect the change in genes after USP53 overexpression and knockdown. Then we tested the effect of USP53 on IκBα protein stability through western blot analysis. Detect the effect of USP53 on IκBα ubiquitination in vitro by immunoprecipitation method.

Results

USP53 expression was downregulated in ccRCC tissues and USP53 expression was significantly negatively correlated with the tumor progression and clinical prognosis. The ability of growth and metastasis of ccRCC was inhibited after USP53 overexpression. In addition, USP53 knockdown promoted ccRCC growth and metastasis. Moreover, USP53 knockdown promoted the ability of clone formation of ccRCC in vivo. NF‐κB signaling pathway significantly enriched and downregulated in USP53 overexpressed cells, and genes in the NF‐κB pathway (such as IL1B, CXCL1‐3, RELA, RELB, etc.) were obviously downregulated in USP53 overexpressed cells. USP53 overexpression decreased the phosphorylation of IKKβ and P65 in both Caki‐1 and 786‐O cells, and the expression of IκBα was increased. Phosphorylation of IKKβ and P65 was increased in both Caki‐1 and 786‐O cells after USP53 knockdown. As the expression of USP53 increases, the protein expression of IκBα was also gradually increased and USP53 reduced the ubiquitination of IκBα.

Conclusion

In summary, our data indicate that USP53 inhibits the inactivation of the NF‐κB pathway by reducing the ubiquitination of IκBα to further inhibit ccRCC proliferation and metastasis. These findings may help understand the pathogenesis of ccRCC and introduce new potential therapeutic targets for kidney cancer patients.

CircCSNK1G3 up-regulates miR-181b to promote growth and metastasis via TIMP3-mediated epithelial to mesenchymal transitions in renal cell carcinoma

Renal cell carcinoma (RCC) is the most common form of kidney cancer, with a high recurrence rate and metastasis capacity. Circular RNAs (circRNAs) have been suggested to act as the critical regulator in several diseases. This study is designed to investigate the role of circCSNK1G3 on RCC progression. We observed a highly expression of circCSNK1G3 in RCC tissues compared with normal tissues. The aberrantly circCSNK1G3 promoted the tumour growth and metastasis in RCC. In the subsequent mechanism investigation, we discovered that the tumour‐promoting effects of circCSNK1G3 were, at least partly, achieved by up‐regulating miR‐181b. Increased miR‐181b inhibits several tumour suppressor gene, including CYLD, LATS2, NDRG2 and TIMP3. Furthermore, the decreased TIMP3 leads to the enhanced epithelial to mesenchymal transition (EMT) process, thus promoting the cancer metastasis. In conclusion, we identified the oncogenic role of circCSNK1G3 in RCC progression and demonstrated the regulatory role of circCSNK1G3 induced miR‐181b expression, which leads to TIMP3‐mediated EMT process, thus resulting in tumour growth and metastasis in RCC. This study reveals the promise of circCSNK1G3 to be developed as a potential diagnostic and prognostic biomarker in the clinic. And the roles of circCSNK1G3 in cancer research deserve further investigation.

Hunting down the dominating subclone of cancer stem cells as a potential new therapeutic target in multiple myeloma: An artificial intelligence perspective

The development of single-cell subclones, which can rapidly switch from dormant to dominant subclones, occur in the natural pathophysiology of multiple myeloma (MM) but is often "pressed" by the standard treatment of MM. These emerging subclones present a challenge, providing reservoirs for chemoresistant mutations. Technological advancement is required to track MM subclonal changes, as understanding MM's mechanism of evolution at the cellular level can prompt the development of new targeted ways of treating this disease. Current methods to study the evolution of subclones in MM rely on technologies capable of phenotypically and genotypically characterizing plasma cells, which include immunohistochemistry, flow cytometry, or cytogenetics. Still, all of these technologies may be limited by the sensitivity for picking up rare events. In contrast, more incisive methods such as RNA sequencing, comparative genomic hybridization, or whole-genome sequencing are not yet commonly used in clinical practice. Here we introduce the epidemiological diagnosis and prognosis of MM and review current methods for evaluating MM subclone evolution, such as minimal residual disease/multiparametric flow cytometry/next-generation sequencing, and their respective advantages and disadvantages. In addition, we propose our new single-cell method of evaluation to understand MM's mechanism of evolution at the molecular and cellular level and to prompt the development of new targeted ways of treating this disease, which has a broad prospect.

Berberine associated photodynamic therapy promotes autophagy and apoptosis via ROS generation in renal carcinoma cells

Renal cell carcinoma (RCC) consists of the most lethal common urological cancer and the clinical practice has shown that resistant RCC to commons therapies is extremely high. Berberine is an isoquinoline alkaloid, presents in different kinds of plants and it has long been used in Chinese medicine. It has several properties, such as antioxidant, anti-inflammatory, anti-diabetic, anti-microbial and anti-cancer. Moreover, berberine has photosensitive characteristics and its association with photodynamic therapy (PDT) is effective against tumor cells. This study aimed to evaluate the effects of berberine associated with PDT in renal carcinoma cell lines. The cellular viability assay showed increased cytotoxicity in concentration and time-dependent manner. Berberine presented efficient internalization in all cell lines analyzed. In addition, after treatment with berberine associated with PDT, it was observed a high phototoxicity effect with less than 20 % of viable cells. In this study we observed that the increase of reactive oxygen species (ROS) levels was accompanied by an increase of autophagy levels and apoptosis by caspase 3 activity, suggesting cell death by both mechanisms. Additionally, three target genes of anti-cancer drugs were differentially expressed in 786-O cells, being that Vascular Endothelial Growth Factor-D (FIGF) and Human Telomerase Reverse Transcriptase (TERT) gene presented low expression and Polo Like Kinase 3 (PLK3) presented overexpression after treatment with berberine associated with PDT. In this study, the proposed treatment triggered metabolites changes related to cell proliferation, tumorigenesis and angiogenesis. Thus, it was possible to suggest that berberine has promising potential as a photosensitizing agent in a photodynamic therapy, because it induced significant anticancer effects on renal carcinoma cells.

Successful Treatment of Veno-occlusive Disease, Transplantation-Associated Thrombotic Microangiopathy, and Acute Graft-vs-Host Disease in a Patient with Relapsed Epstein-Barr Hemophagocytic Lymphohistiocytosis After Haploidentical Hematopoietic Stem Cell Transplantation: A Case Report

BACKGROUND

Allogenic hematopoietic stem cell transplantation may be the best currently available method to treat relapsed hemophagocytic lymphohistiocytosis (HLH) related to Epstein-Barr virus. The high rate of transplantation-related complications was initially the main obstacle preventing the wider adoption of this protocol; however, the previously more common complications, such as infection and graft failure, have fallen to very low levels with the development of new drugs and methods. Some other complications, such as veno-occlusive disease and transplantation associated thrombotic microangiopathy, are rare after allogenic hematopoietic stem cell transplantation, but the morbidity and mortality associated with them are very high.

CASE PRESENTATION

A patient with relapsed HLH related to Epstein-Barr virus showed the sequential severe complications of veno-occlusive disease, transplantation-associated thrombotic microangiopathy, and acute graft-vs-host disease after haploidentical transplantation. This patient was successfully treated by stopping administration of calcineurin inhibitors and instead treating with defibrotide, rituximab, CD25 monoclonal antibody, atorvastatin calcium tablets, methylprednisolone, budesonide, continuous plasma exchange, and bedside ultrafiltration. At the last follow-up, the patient had been living disease free for 2 years without any other complications.

CONCLUSION

Epstein-Barr virus related-HLH patients have severe clinical features and currently poor prognosis. Allogenic hematopoietic stem cell transplantation may be the best way to treat this disease; however, the management of related complications is vital in the improvement of long-term survival.

Spatiotemporal switching signals for cancer stem cell activation in pediatric origins of adulthood cancer: Towards a watch-and-wait lifetime strategy for cancer treatment

Pediatric origin of cancer stem cell hypothesis holds great promise and potential in adult cancer treatment, however; the road to innovation is full of obstacles as there are plenty of questions left unanswered. First, the key question is to characterize the nature of such stem cells (concept). Second, the quantitative imaging of pediatric stem cells should be implemented (technology). Conceptually, pediatric stem cell origins of adult cancer are based on the notion that plasticity in early life developmental programming evolves local environments to cancer. Technologically, such imaging in children is lacking as all imaging is designed for adult patients. We postulate that the need for quantitative imaging to measure space-time changes of plasticity in early life developmental programming in children may trigger research and development of the imaging technology. Such quantitative imaging of pediatric origin of adulthood cancer will help develop a spatiotemporal monitoring system to determine cancer initiation and progression. Clinical validation of such speculative hypothesis-that cancer originates in a pediatric environment-will help implement a wait-and-watch strategy for cancer treatment.

Long noncoding RNA PVT1 inhibits renal cancer cell apoptosis by up-regulating Mcl-1

Long non-coding RNA plasmacytoma variant translocation 1 (PVT1) is up-regulated in various human cancers, and our results indicated that PVT1 was up-regulated in clear cell renal cell carcinoma tissues. The Cancer Genome Atlas cohort analysis revealed that in clear cell renal cell carcinoma, higher PVT1 expression correlated with advanced TNM stage, histological grade, and poor survival. PVT1 knockdown promoted apoptosis, inhibited renal cancer cell proliferation, decreased Mcl-1, and increased cleaved caspase-3 and cleaved PARP. PVT1 increased Mcl-1 mRNA levels in renal cancer cells by promoting mRNA stability without influencing its transcription. in vitro, the enhanced apoptosis arising from PVT1 suppression was attenuated by overexpressing Mcl-1. In addition, in vivo experiments showed that PVT1 knockdown repressed xenograft tumor growth, while Mcl-1 overexpression partially rescued xenograft tumor growth. These results indicate the PVT1/Mcl-1 pathway inhibits renal cancer cell apoptosis in vitro and in vivo. PVT1 may thus serve as a novel biomarker, and the PVT1/Mcl-1 pathway may be a useful therapeutic target for clear cell renal cell carcinoma.

The Expression of Fibroblast Activation Protein in Clear Cell Renal Cell Carcinomas Is Associated with Synchronous Lymph Node Metastases

Clear cell renal cell carcinoma (CCRCC) is a heterogeneous and complex disease that frequently develops distant metastases. Fibroblast activation protein (FAP) is a serine peptidase the expression of which in cancer-associated fibroblasts has been associated with higher risk of metastases and poor survival. The objective of this study was to evaluate the role of FAP in metastatic CCRCC (mCCRCC). A series of 59 mCCRCC retrospectively collected was included in the study. Metastases developed either synchronous (n = 14) or metachronous to renal disease (n = 45). Tumor specimens were obtained from both primary lesion (n = 59) and metastases (n = 54) and FAP expression was immunohistochemically analyzed. FAP expression in fibroblasts from primary tumors correlated with FAP expression in the corresponding metastatic lesions. Also, primary and metastatic FAP expression was correlated with large tumor diameter (>7cm), high grade (G3/4), high stage (pT3/4), tumor necrosis and sarcomatoid transformation. The expression of FAP in primary tumors and in their metastases was associated both with synchronous metastases and also with metastases to the lymph nodes. FAP expression in the primary tumor was correlated with worse 10-year overall survival. Immunohistochemical detection of FAP in the stromal tumor fibroblasts could be a biomarker of early lymph node metastatic status and therefore could account for the poor prognosis of FAP positive CCRCC.