Prognostic value of intratumoral carbonic anhydrase IX expression in testicular germ cell tumors

Evolutionary determinants of curability in cancer

The emergence of drug-resistant cells, most of which have a mutated TP53 gene, prevents curative treatment in most advanced and common metastatic cancers of adults. Yet, a few, rarer malignancies, all of which are TP53 wild type, have high cure rates. In this Perspective, we discuss how common features of curable cancers offer insights into the evolutionary and developmental determinants of drug resistance. Acquired loss of TP53 protein function is the most common genetic change in cancer. This probably reflects positive selection in the context of strong ecosystem pressures including microenvironmental hypoxia. Loss of TP53's functions results in multiple fitness benefits and enhanced evolvability of cancer cells. TP53-null cells survive apoptosis, and tolerate potent oncogenic signalling, DNA damage and genetic instability. In addition, critically, they provide an expanded pool of self-renewing, or stem, cells, the primary units of evolutionary selection in cancer, making subsequent adaptation to therapeutic challenge by drug resistance highly probable. The exceptional malignancies that are curable, including the common genetic subtype of childhood acute lymphoblastic leukaemia and testicular seminoma, differ from the common adult cancers in originating prenatally from embryonic or fetal cells that are developmentally primed for TP53-dependent apoptosis. Plus, they have other genetic and phenotypic features that enable dissemination without exposure to selective pressures for TP53 loss, retaining their intrinsic drug hypersensitivity.

Advances in diagnosis and treatment of testicular cancer

Testicular cancer is a curable cancer. The success of physicians in curing the disease is underpinned by multidisciplinary advances. Cisplatin-based combination chemotherapy and the refinement of post-chemotherapy surgical procedures and diagnostic strategies have greatly improved long term survival in most patients. Despite such excellent outcomes, several controversial dilemmas exist in the approaches to clinical stage I disease, salvage chemotherapy, post-chemotherapy surgical procedures, and implementing innovative imaging studies. Relapse after salvage chemotherapy has a poor prognosis and the optimal treatment is not apparent. Recent research has provided insight into the molecular mechanisms underlying cisplatin resistance. Phase 2 studies with targeted agents have failed to show adequate efficacy; however, our understanding of cisplatin resistant disease is rapidly expanding. This review summarizes recent advances and discusses relevant issues in the biology and management of testicular cancer.

Immunohistochemistry for the diagnosis of renal epithelial neoplasms

Despite the increasing number of newly identified renal neoplasms, the diagnosis of renal cell carcinoma (RCC) can usually be reached with careful histologic examination and a limited immunohistochemical (IHC) panel. Clear cell, papillary, chromophobe RCC and oncocytoma account for more than 90% of renal neoplasia in adults, and sophisticated ancillary tools are usually unnecessary. Renal tumors with entity-defining genetic alterations may ultimately require molecular confirmation via cytogenetics or sequencing technologies, such as RCC with TFE3, TFEB, or ALK gene rearrangements, or TFEB amplified RCC. In fumarate hydratase-deficient and succinate dehydrogenase-deficient RCC, highly specific IHC markers can strongly suggest the diagnosis. In the metastatic setting, PAX8 and carbonic anhydrase 9 are among the most helpful markers for confirming RCC and clear cell type, respectively; however, caution should be exercised in the absence of a current or historical renal mass. In diagnostically challenging cases, such as renal eosinophilic tumors with low-grade nuclear features, or infiltrative high-grade tumors, careful examination coupled with a judicious panel of IHC markers usually resolves the diagnosis. This review offers concise algorithms for diagnosis of kidney neoplasia with the latest recognized, provisional, and emerging entities to daily pathology practice.

Screening for the Key Proteins Associated with Rete Testis Invasion in Clinical Stage I Seminoma via Label-Free Quantitative Mass Spectrometry

Rete testis invasion (RTI) is an unfavourable prognostic factor for the risk of relapse in clinical stage I (CS I) seminoma patients. Notably, no evidence of difference in the proteome of RTI-positive vs. -negative CS I seminomas has been reported yet. Here, a quantitative proteomic approach was used to investigate RTI-associated proteins. 64 proteins were differentially expressed in RTI-positive compared to -negative CS I seminomas. Of them, 14-3-3γ, ezrin, filamin A, Parkinsonism-associated deglycase 7 (PARK7), vimentin and vinculin, were validated in CS I seminoma patient cohort. As shown by multivariate analysis controlling for clinical confounders, PARK7 and filamin A expression lowered the risk of RTI, while 14-3-3γ expression increased it. Therefore, we suggest that in real clinical biopsy specimens, the expression level of these proteins may reflect prognosis in CS I seminoma patients.

Post-translational modifications in tumor-associated carbonic anhydrases

Human carbonic anhydrases IX (hCA IX) and XII (hCA XII) are two proteins associated with tumor formation and development. These enzymes have been largely investigated both from a biochemical and a functional point of view. However, limited data are currently available on the characterization of their post-translational modifications (PTMs) and the functional implication of these structural changes in the tumor environment. In this review, we summarize existing literature data on PTMs of hCA IX and hCA XII, such as disulphide bond formation, phosphorylation, O-/N-linked glycosylation, acetylation and ubiquitination, highlighting, when possible, their specific role in cancer pathological processes.

SPANXN2 functions a cell migration inhibitor in testicular germ cell tumor cells

Background

SPANX family members are thought to play an important role in cancer progression. The SPANXN2 is a gene expressed mainly in normal testis, but its role in testicular germ cell tumors (TGCTs) has yet to be investigated. TGCT is one of the most common solid tumors in young men and is associated with poor prognosis; however, effective prognostic indicators remain elusive. Therefore, we investigated the role of SPANXN2 in TGCT development.

Methods

SPANXN2 expression levels were validated by quantitative real-time polymerase chain reaction (qRT-PCR) analyses of 14 TGCT samples and five adjacent normal tissue samples. SPANXN2 was transiently overexpressed in TGCT cells to study the consequences for cell function. The effects of SPANXN2 on cell migration were evaluated in transwell and wound healing assays. The effects on cloning ability were evaluated in colony formation assays. MTT assays and cell cycle analysis were used to detect the effects of SPANXN2 on cell proliferation. The expression levels of EMT- and AKT-related proteins in cells overexpressing SPANXN2 were analyzed by Western blotting.

Results

Compared with adjacent normal tissues, the Gene Expression Profiling Interactive Analysis database showed SPANXN2 expression was downregulated in TGCTs which was consistent with the qRT-PCR analysis. SPANXN2 overexpression reduced cell migration and colony formation capability and downregulated expression of EMT- and AKT-related proteins, Vimentin, Snail, AKT, and p-AKT.

Conclusion

Our results suggest that SPANXN2 regulates TGCT cell migration via EMT- and AKT-related proteins although its role in the occurrence and development of TGCT remains to be fully elucidated.

The metabolic landscape of urological cancers: New therapeutic perspectives

Deregulation of cell metabolism is an established cancer hallmark that contributes to tumor initiation and progression, as well as tumor heterogeneity. In solid tumors, alterations in different metabolic pathways, including glycolysis, pentose phosphate pathway, glutaminolysis and fatty acid metabolism, support the high proliferative rates and macromolecule biosynthesis of cancer cells. Despite advances in therapy, urothelial tumors still exhibit high recurrence and mortality rates, especially in advanced stages of disease. These tumors harbor gene mutations and expression patterns which play an important role in metabolic reprogramming. Taking into account the unique metabolic features underlying carcinogenesis in these cancers, new and promising therapeutic targets based on metabolic alterations must be considered. Furthermore, the combination of metabolic inhibitors with conventional targeted therapies may improve effectiveness of treatments. This review will summarize the metabolic alterations present in urological tumors and the results with metabolic inhibitors currently available.

Prognostic markers in clinical stage I seminoma and nonseminomatous germ cell tumours

PURPOSE OF REVIEW

Testicular germ cell tumour (TGCT) is a common malignancy among young men. There is controversy regarding the best approach for patients with clinical stage I disease due to rates of relapse with active surveillance in contrast to overtreatment with adjuvant therapy. The aim of this review is to describe the role of prognostic factors in this setting.

RECENT FINDINGS

Molecular prognostic factors have been described as a possible future aid to clinical and histologic features in the approach of patients with clinical stage I germ cell tumours.

SUMMARY

Prognostic factors currently available are not accurate enough and may lead to overtreatment. However, though active surveillance has shown long-term survival near to 100% in the management of clinical stage I germ cell tumours, there is a significant percentage of patients with occult metastatic disease, who benefit from adjuvant therapy. In light of these data, future research is needed to better define high-risk patients for relapse, taking into account molecular markers recently reported.

The Warburg Effect Is Associated With Tumor Aggressiveness in Testicular Germ Cell Tumors

Testicular Germ Cell Tumors (TGCTs) are a rare group of neoplasms and the most common solid malignancy arising in young male adults. Despite the good response of these tumors to platinum-based chemotherapy, some patients are refractory to treatment and present poor clinical outcomes. During carcinogenesis and tumor development, cancer cells reprogram energy metabolism toward a hyper-glycolytic phenotype, an emerging hallmark of cancer. This phenomenon, known as the Warburg effect or aerobic glycolysis, involves overexpression of metabolism-related proteins, like glucose and monocarboxylate transporters, pH regulators and intracellular glycolytic enzymes. The metabolic profile of TGCTs is very little explored and, recently, this metabolic rewiring of cancer cells has been associated with aggressive clinicopathological characteristics of these tumors. The overexpression of monocarboxylate transporter 4 (MCT4) in TGCTs has been pointed out as a poor prognostic factor, as well as a promising therapeutic target. As a result, the main aim of the present study was to evaluate the prognostic value of key metabolism-related proteins in TGCTs. The immunohistochemical expressions of CD44 (as a monocarboxylate transporter chaperone), glucose transporter 1 (GLUT1), carbonic anhydrase IX (CAIX), hexokinase II (HKII) and lactate dehydrogenase V (LDHV) were evaluated in a series of 148 adult male patients with TGCTs and associated with clinicopathological parameters. In addition, paired normal tissues were also evaluated. The sample included 75 seminoma and 73 non-seminoma tumors. GLUT1 and CD44 expression was significantly increased in malignant samples when compared to paired normal samples. Conversely, HKII and LDHV expressions were significantly decreased in malignant samples. Concerning the clinicopathological values, CAIX expression was significantly associated with disease recurrence, while HKII expression was significantly associated with aggressive characteristics of TGCTs, including higher staging and non-seminoma histology. In conclusion, this study brings new insights on the metabolic characteristics of TGCTs, showing alterations in the expression of proteins related with the Warburg effect, as well as associations of the hyper-glycolytic and acid-resistant phenotype with aggressive clinicopathological parameters.

Emerging Prognostic Biomarkers in Testicular Germ Cell Tumors: Looking Beyond Established Practice

Testicular germ cell tumors are unique among solid cancers. Historically, this disease was deadly if progressed beyond the stage I. The implementation of cisplatin-based chemotherapy regimens has drastically changed the clinical outcome of metastatic testicular cancer. Several biomarkers were established to refine the prognosis by International Germ Cell Collaborative Group in 1997. Among these, the most significant were primary tumor site; metastatic sites, such as non-pulmonary visceral metastases; and the amplitude of serum tumor markers α-fetoprotein, β-chorionic gonadotropin, and lactate dehydrogenase. Since then, oncology has experienced discoveries of various molecular biomarkers to further refine the prognosis and treatment of malignancies. However, the ability to predict the prognosis and treatment response in germ cell tumors did not improve for many years. Clinical trials with novel targeting agents that were conducted in refractory germ cell tumor patients have proven to have negative outcomes. With the recent advances and developments, novel biomarkers emerge in the field of germ cell tumor oncology. This review article aims to summarize the current knowledge in the research of novel prognostic biomarkers in testicular germ cell tumors.

Inhibition of carbonic anhydrase IX targets primary tumors, metastases, and cancer stem cells: Three for the price of one

Human carbonic anhydrase (CA) IX is a tumor-associated protein, since it is scarcely present in normal tissues, but highly overexpressed in a large number of solid tumors, where it actively contributes to survival and metastatic spread of tumor cells. Due to these features, the characterization of its biochemical, structural, and functional features for drug design purposes has been extensively carried out, with consequent development of several highly selective small molecule inhibitors and monoclonal antibodies to be used for different purposes. Aim of this review is to provide a comprehensive state-of-the-art of studies performed on this enzyme, regarding structural, functional, and biomedical aspects, as well as the development of molecules with diagnostic and therapeutic applications for cancer treatment. A brief description of additional pharmacologic applications for CA IX inhibition in other diseases, such as arthritis and ischemia, is also provided.

Transcriptome analysis of human colorectal cancer biopsies reveals extensive expression correlations among genes related to cell proliferation, lipid metabolism, immune response and collagen catabolism

Precise characterization of biological processes critical to proliferation and metastasis of colorectal cancer should facilitate the development of diagnostic and prognostic biomarkers as well as novel treatments. Using mRNA-Seq, we examined the protein coding messenger RNA (mRNA) expression profiles across different histologically defined stages of primary colon cancers and compared them to their patient matched normal tissue controls. In comparing 79 colorectal cancers to their matched normal mucosa, tumors were distinguished from normal non-malignant tissues not only in the upregulation of biological processes pertaining to cell proliferation, inflammation, and tissue remodeling, but even more strikingly, in downregulated biological processes including fatty acid beta oxidization for ATP production and epithelial cell differentiation and function. A network analysis of deregulated genes revealed newly described cancer networks and putative hub genes.

Taken together, our findings suggest that, within an inflammatory microenvironment, invasive, dedifferentiated and rapidly dividing tumor cells divert the oxidation of fatty acids and lipids from energy production into lipid components of cell membranes and organelles to support tumor proliferation. A gene co-expression network analysis provides a clear and broad picture of biological pathways in tumors that may significantly enhance or supplant current histopathologic studies.