D9S168 microsatellite alteration predicts a poor prognosis in patients with clear cell renal cell carcinoma and correlates with the down-regulation of protein tyrosine phosphatase receptor delta

Case Report: Clinical complete response of advanced renal cell carcinoma associated with Xp11.2 translocation/TFE3 gene fusion by treated by camrelizumab and axitinib: A rare case report

Renal cell carcinoma (RCC) associated with Xp11.2 translocation/TFE3 gene fusions is a rare subtype of renal tumor. This entity predominantly occurs in juveniles, but rarely in adults. Xp11.2 translocation RCC (tRCC) patients with lymph node or organ metastasis are associated with poor prognosis, and the strategy remains controversial. Herein, we presented our experience with the diagnosis and treatment of an adult case of Xp11.2 tRCC. In our clinical practice, a 32-year-old male manifested fever and right flank paroxysmal blunt pain, and computed tomography showed an inhomogeneous mass, 6 cm in diameter, in the right kidney. Then right partial nephrectomy (PN) and renal hilar lymph node dissection by laparoscopic surgery were performed. Pathology revealed that the tumor cells were positive for TFE3 immunohistologically and positive for TFE3 break-apart fluorescence in situ hybridization assay. A splice site mutation c.1544-1G>T of protein tyrosine phosphatase receptor delta (PTPRD) was detected by next-generation sequencing and weak PTPRD expression was confirmed in tumor tissues compared to tumor periphery. This patient was diagnosed with stage III RCC and received immune checkpoint inhibitor (camrelizumab) in combination with tyrosine kinase inhibitor (axitinib) treatment for 1 year. He achieved a clinical complete response with no sign of recurrence or metastasis. PTPRD mutation might be a favorable indicator for Xp11.2 tRCC patients managed by PN and followed by the adjuvant therapy of immune checkpoint inhibitor and tyrosine kinase inhibitor.

HBV preS Mutations Promote Hepatocarcinogenesis by Inducing Endoplasmic Reticulum Stress and Upregulating Inflammatory Signaling

Simple Summary

Viral mutations at the preS region of hepatitis B virus (HBV) significantly increase the risk of developing hepatocellular carcinoma (HCC). Compared to HBV preS deletion, the oncogenic effect of preS combo mutation has rarely been investigated. With a cohort including 2114 subjects, we demonstrated that preS combo mutations G2950A/G2951A/A2962G/C2964A and C3116T/T31C significantly increased the risk of HCC in patients without antiviral treatment, whereas preS2 deletion significantly increased the risk of HCC in patients with antiviral treatment. The prevalence of C3116T/T31C (43.61%) was higher than preS2 deletion (7.16%). By using Sleeping Beauty mouse models and in vitro experiments, we found G2950A/G2951A/A2962G/C2964A, C3116T/T31C, and preS2 deletion promoted hepatocarcinogenesis by increasing levels of inflammatory cytokines, activating STAT3 pathway, enhancing endoplasmic reticulum stress, and altering gene expression profiles in inflammation- and metabolism-related pathways. These results suggest that preS combo mutations G2950A/G2951A/A2962G/C2964A and C3116T/T31C had similar oncogenic effects of preS2 deletion and should also be monitored.

Abstract

This study aimed to elucidate the effects and underlying mechanisms of hepatitis B virus (HBV) preS mutations on hepatocarcinogenesis. The effect of the preS mutations on hepatocellular carcinoma (HCC) occurrence was evaluated using a prospective cohort study with 2114 HBV-infected patients, of whom 612 received antiviral treatments. The oncogenic functions of HBV preS mutations were investigated using cancer cell lines and Sleeping Beauty (SB) mouse models. RNA-sequencing and microarray were applied to identify key molecules involved in the mutant-induced carcinogenesis. Combo mutations G2950A/G2951A/A2962G/C2964A and C3116T/T31C significantly increased HCC risk in patients without antiviral treatment, whereas the preS2 deletion significantly increased HCC risk in patients with antiviral treatment. In SB mice, the preS1/preS2/S mutants induced a higher rate of tumor and higher serum levels of inflammatory cytokines than did wild-type counterpart. The preS1/preS2/S mutants induced altered gene expression profiles in the inflammation- and metabolism-related pathways, activated pathways of endoplasmic reticulum (ER) stress, affected the response to hypoxia, and upregulated the protein level of STAT3. Inhibiting the STAT3 pathway attenuated the effects of the preS1/preS2/S mutants on cell proliferation. G2950A/G2951A/A2962G/C2964A, C3116T/T31C, and preS2 deletion promote hepatocarcinogenesis via inducing ER stress, metabolism alteration, and STAT3 pathways, which might be translated into HCC prophylaxis.

Integrative Analysis of the Genomic and Immune Microenvironment Characteristics Associated With Clear Cell Renal Cell Carcinoma Progression: Implications for Prognosis and Immunotherapy

Unlike early clear cell renal cell carcinoma (ccRCC), locally advanced and metastatic ccRCC present poor treatment outcomes and prognosis. As immune checkpoint inhibitors have achieved favorable results in the adjuvant treatment of metastatic ccRCC, we aimed to investigate the immunogenomic landscape during ccRCC progression and its potential impact on immunotherapy and prognosis. Using multi-omics and immunotherapy ccRCC datasets, an integrated analysis was performed to identify genomic alterations, immune microenvironment features, and related biological processes during ccRCC progression and evaluate their relevance to immunotherapy response and prognosis. We found that aggressive and metastatic ccRCC had higher proportions of genomic alterations, including SETD2 mutations, Del(14q), Del(9p), and higher immunosuppressive cellular and molecular infiltration levels. Of these, the Del(14q) might mediate immune escape in ccRCC via the VEGFA-VEGFR2 signaling pathway. Furthermore, immune-related pathways associated with ccRCC progression did not affect the immunotherapeutic response to ccRCC. Conversely, cell cycle pathways not only affected ccRCC progression and prognosis, but also were related to ccRCC immunotherapeutic response resistance. Overall, we described the immunogenomic characteristics of ccRCC progression and their correlations with immunotherapeutic response and prognosis, providing new insights into their prediction and the development of novel therapeutic strategies.

Assessing Genomic Copy Number Alterations as Best Practice for Renal Cell Neoplasia: An Evidence-Based Review from the Cancer Genomics Consortium Workgroup

Renal cell neoplasia are heterogeneous with diverse histology, genetic alterations, and clinical behavior that are diagnosed mostly on morphologic features. The Renal Cell Neoplasia Workgroup of the Cancer Genomics Consortium systematically evaluated peer-reviewed literature on genomic studies of renal cell carcinoma (RCC), including clear cell RCC, papillary RCC, chromophobe RCC, and the translocation RCC involving TFE3, TFEB and MITF rearrangements, as well as benign oncocytoma, which together comprise about 95% of all renal cell neoplasia. The Workgroup curated recurrent copy number alterations (CNAs), copy-neutral loss-of-heterozygosity (cnLOH), rearrangements, and mutations, found in each subtype and assigned clinical relevance according to established criteria. In clear cell RCC, loss of 3p has a disease-initiating role and most likely also in progression with mutations detected in VHL and other genes mapped to this arm, and loss of 9p and/or 14q has well-substantiated prognostic utility. Gain of chromosomes 7 and 17 are hallmark CNAs of papillary RCC, but patterns of other CNAs as detected by chromosomal microarray analysis (CMA) afford sub-classification into Type 1 and 2 with prognostic value, and for further sub-stratification of Type 2. Inherent chromosome loss in chromophobe RCC as detected by CMA is useful for distinguishing the eosinophilic variant from benign oncocytoma which in contrast exhibits few CNAs or rearranged CCND1, but share mitochondrial DNA mutations. In morphologically atypical RCCs, rearrangement of TFE3 and TFEB should be considered in the differential diagnosis, portending an aggressive RCC subtype. Overall, this evidence-based review provides a validated role for assessment of CNAs in renal cell neoplasia in the clinical setting to assist in renal cell neoplasm diagnosis and sub-classification within subtypes that is integral to the management of patients, from small incidentally found renal masses to larger surgically resected specimens, and simultaneously identify the presence of key alterations portending outcome in malignant RCC subtypes.

Chromosomal deletion of 9p21 is linked to poor patient prognosis in papillary and clear cell kidney cancer

BACKGROUND

The ongoing approval of adjuvant systemic therapy in high-risk kidney tumor will increase the demand for prognostic assessment in these tumors. 9p21 deletion has been suggested as a possible prognostic feature in clear cell kidney cancer.

MATERIAL AND METHODS

To learn more on the prognostic relevance of 9p21 deletions in clear cell and other kidney tumors, 1,809 kidney tumor specimens were analyzed by dual-labeling fluorescence in situ hybridization (FISH) with probes for 9p21 and centromere 9 in a tissue microarray format. Results were compared to histologic tumor type, pT stage, grade, and patient outcome.

RESULTS

A total of 1,341 (74%) of tumor samples had interpretable FISH results. 9p21 deletion was found in 4.4% of 894 clear cell, 5.1% of 197 papillary, and 4.2% of 71 chromophobe carcinomas. 9p21 deletions were not found in 112 oncocytomas and in 21 clear cell tubulo-papillary cancers. In clear cell carcinomas, 9p deletions were associated with advanced stage (P = 0.009) and nodal metastasis (P = 0.0067), but not with ISUP grade (P = 0.1039) and distant metastasis (P = 0.4809). Also, in papillary carcinomas, 9p deletions were associated with advanced stage (P = 0.0008) and nodal metastasis (P = 0.0202) but not with ISUP grade (0.0904) and distant metastasis (P = 0.2022). Follow-up data were available for 789 clear cell and 177 papillary cancers. In both tumor entities, 9p21 deletions were associated with shortened overall survival, tumor-specific death, and progression-free survival in univariate analysis (P < 0.02 each). In a multivariate analysis, 9p21 deletion was an independent predictor of early tumor recurrence (P = 0.04).

CONCLUSION

9p21 deletions, 9p21 deletions identify a small subset of aggressive renal carcinomas. 9p deletion assessment may be clinically useful to identify high-risk renal cell carcinomas.

A Meta-Analysis Evaluating Clinical Outcomes of Patients with Renal Cell Carcinoma Harboring Chromosome 9P Loss

CONTEXT

9p loss appears a reliable and promising marker able to differentiate specific categories of patients with renal cell carcinoma associated with a worse prognosis.

OBJECTIVE

The aim was to systematically evaluate relative risk of death, cancer-specific survival (CSS) and disease-free survival (DFS) among patients harboring 9p loss.

EVIDENCE SYNTHESIS

We found a total of 92 potentially relevant articles focused on the detection of 9p loss in patients with renal cell carcinoma and clinical outcomes of this population. Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) guidelines were employed to carry out this work. Fourteen studies resulted to be eligible for this analysis; 11 of these reported data on 5-year overall survival, six on CSS and four on DFS. An increased risk of death has been observed in patients harboring 9p loss (pooled relative risk of 3.965; 95% confidence interval [CI] 2.647-5.940, p < 0.001). Similarly, worse CSS (hazard ratio [HR] 6.776; 95% CI 3.824-12.009; p < 0.001) and DFS (HR 2.914; 95% CI 1.245-6.819; p = 0.014) have been observed in this population. Heterogeneity was significant in survival analysis, while no significant heterogeneity was observed in the CSS and DFS analyses.

CONCLUSIONS

Patients harboring chromosome 9p loss have worse clinical outcomes in terms of overall survival, CSS and DFS.

Monosomy of Chromosome 9 Is Associated With Higher Grade, Advanced Stage, and Adverse Outcome in Clear-cell Renal Cell Carcinoma

BACKGROUND

Clear-cell renal cell carcinoma (ccRCC) is one of the most common malignancies in humans and is usually associated with poor outcomes. Cancers are considered to be genetic diseases. Therefore, a better understanding of genetic alterations that are related to disease progression or poor prognosis can help to more precisely identify high-risk patients and treat them more effectively. The aim of this study was to examine the frequency of whole chromosome 9 loss (monosomy of chromosome 9) and its prognostic value in patients with ccRCC.

MATERIALS AND METHODS

Single nucleotide polymorphism-based chromosome microarray (CMA) analysis was performed on 103 resected specimens from patients with ccRCC who had undergone partial or radical nephrectomy between January 2002 and March 2017 at Fox Chase Cancer Center. Monosomy 9 was correlated with clinicopathologic parameters and recurrence-free survival.

RESULTS

Chromosome 9 loss was detected in 31 (30%) of 103 tumors. Tumors with chromosome 9 loss had higher histologic grade (3 and 4; P < .001) and pathologic stage (P < .001). In 59 patients with non-metastatic ccRCC, chromosome 9 loss was also associated with higher recurrence rate and shorter recurrence-free survival (RFS) (12-month RFS, 77.8%; 95% confidence interval, 36.5%-93.9% for chromosome 9 loss vs. 95.7%; 95% confidence interval, 84.0%-98.9% for no loss; P = .002).

CONCLUSIONS

Chromosome 9 loss was found in 30% of patients with ccRCC and correlated with higher grade, advanced stage, and shorter RFS in patients with Stage I to III ccRCC.

Tumour suppressor gene (CDKNA2) status on chromosome 9p in resected renal tissue improves prognosis of localised kidney cancer

Background

Genetic alterations on chromosome 9p, including inactivation of the tumour suppressor gene, CDKN2A, result in cellular proliferation and growth of tumours. Our aim was to use microsatellite analysis and fluorescence in situ hybridization (FISH) to characterise the architecture of this region.

Results

Seventy-five out of 77 clear cell renal cell cancers (tumour/normal pairs) were interpretable for LOH analysis on chromosome 9p (two tumours were excluded, as all five primers were uninformative). Twenty out of 75 (26.6%) tumours showed LOH in at least one of the five primers employed. Most allelic deletions were detected, telomeric to the CDKN2A region at D9S916, with 11 out of 52 informative tumours (21%) displaying LOH. The LOH in the coding region of CDKN2A, at D9S974 and D9S942, was associated with a higher pT-stage (p = 0.004) and metastasis (p = 0.006, both markers). The rate of chromosome 9p deletion in ccRCC was 44% (35/80 cases) according to FISH. Somatic copy number loss of chromosome 9p was associated with a larger tumour size (p = 0.002), higher pathological tumour stage (p = 0.021), presence of tumour necrosis (p = 0.019) and microvascular invasion (p = 0.032). The cases with copy number loss, loss of heterozygosity and copy number neutral (n = 42) were at a higher risk of cancer-specific death when compared to tumours in category D (n = 32) (Log-rank: p = 0.001). Seventeen patients with localised ccRCC developed recurrence, and fourteen of those showed either LOH or somatic copy number loss at CDKN2A (Log-rank: p = 0.005). Multivariate analysis showed that LOH or copy number loss at CDKN2A retained its independent prognostic effect, improving the predictive accuracy of stage and SSIGN score by concordance Index C from 0.823 to 0.878 (p = 0.001).

Materials and Methods

Cytogenetics data, microsatellite analysis and FISH were acquired for a cohort of patients undergoing resection for clinically localised renal cancer between January 2001 and December 2005. Five microsatellite markers (D9S916, D9S1814, D9S974, D9S942 and D9S171) assessed loss of heterogeneity (LOH) using DNA samples and in the same cohort FISH analysis was accomplished on tissue microarray slides. The FISH data were scored by two observers blinded to the histological data of the patients. Cytogenetic aberrations were correlated with histological and clinical outcomes by univariate and multivariate analyses using different prognostic models. Disease specific and recurrence free survival based on cytogenetic changes were assessed by Kaplan Meier methods.

Conclusions

A comprehensive cytogenetic analysis using microsatellite analysis and FISH of the CDKN2A region on chromosome 9p improves the predictive accuracy of known prognostic factors in clinically localised renal cell carcinoma undergoing surgical resection.

Follistatin-like protein 1 plays a tumor suppressor role in clear-cell renal cell carcinoma

BACKGROUND

We previously showed that the expression of follistatin-like protein 1 (FSTL1) was significantly down-regulated in metastatic clear-cell renal cell carcinoma (ccRCC). In this study, we aimed to characterize the role of FSTL1 in the development of ccRCC.

METHODS

The effects of FSTL1 on cell activity and cell cycle were investigated in ccRCC cell lines with altered FSTL1 expression. Gene expression microarray assays were performed to identify the major signaling pathways affected by FSTL1 knockdown. The expression of FSTL1 in ccRCC and its effect on postoperative prognosis were estimated in a cohort with 89 patients.

RESULTS

FSTL1 knockdown promoted anchorage-independent growth, migration, invasion, and cell cycle of ccRCC cell lines, whereas FSTL1 overexpression attenuated cell migration. FSTL1 knockdown up-regulated nuclear factor-κB (NF-κB) and hypoxia-inducible factor (HIF) signaling pathways, increased epithelial-to-mesenchymal transition, up-regulated interleukin-6 expression, and promoted tumor necrosis factor-α-induced degradation of NF-κB inhibitor (IκBα) in ccRCC cell lines. FSTL1 immunostaining was selectively positive in epithelial cytoplasm in the loop of Henle, and positive rate of FSTL1 was significantly lower in ccRCC tissues than in adjacent renal tissues (P < 0.001). The multivariate Cox regression analysis showed that the intratumoral FSTL1 expression conferred a favorable independent prognosis with a hazard ratio of 0.325 (95% confidence interval 0.118-0.894). HIF-2α expression was negatively correlated with FSTL1 expression in ccRCC specimens (r = - 0.229, P = 0.044). Intratumoral expression of HIF-2α, rather than HIF-1α, significantly predicted an unfavorable prognosis in ccRCC (log-rank, P = 0.038).

CONCLUSIONS

FSTL1 plays a tumor suppression role possibly via repressing the NF-κB and HIF-2α signaling pathways. To increase FSTL1 expression might be a candidate therapeutic strategy for metastatic ccRCC.

Protein tyrosine phosphatase receptor-type δ acts as a negative regulator suppressing breast cancer

Protein tyrosine phosphatase receptor-type δ (PTPRD) is frequently inactivated in human cancers. This study investigated the role of PTPRD in the regulation of stemness, epithelial-mesenchymal transition (EMT), and migration and invasion in breast cancer cells. In vitro, PTPRD silencing using siRNA enhanced the stem cell-like properties of breast cancer cells, including their mammosphere- and holoclone-forming abilities, and it promoted tumorigenicity in vivo. PTPRD knockdown also increased the CD44⁺/CD24⁻ breast cancer stem cell (BCSC) population and the expression of the stem cell markers ALDH1 and OCT4. It also promoted migration and invasion by breast cancer cell, EMT, and activation of signal transducer and activator of transcription 3 (STAT3). BCSCs expressed low levels of PTPRD, displayed mesenchymal phenotypes, and were more sensitive to IL-6-mediated STAT3 activation than non-BCSCs. PTPRD expression was upregulated by IL-6 in breast cancer cells, thereby establishing a negative feedback circuit by which IL-6 induced canonical STAT3 phosphorylation and transiently upregulated PTPRD, which in turn dephosphorylated STAT3 and prevented downstream signaling via the IL-6/STAT3 cascade. These data suggest that therapies aimed at restoring or enhancing PTPRD expression may be effective in controlling breast cancer progression and metastasis.

Periostin expression in intra-tumoral stromal cells is prognostic and predictive for colorectal carcinoma via creating a cancer-supportive niche

Periostin (POSTN) expression in cancer cells and circulation has been related to poor prognosis of colorectal carcinoma (CRC). However, the role of POSTN expressed in intra-tumoral stroma on CRC progression remains largely unknown. This study enrolled 1098 CRC patients who received surgical treatment in Shanghai and Guangzhou, Mainland China. In Shanghai cohort, immunohistochemistry score of stromal POSTN expression increased consecutively from adjacent mucosa, primary CRC tissues, to metastatic CRC tissues (P < 0.001), while medium- and high-stromal POSTN expression, rather than epithelial POSTN expression, independently predicted unfavorable prognoses of CRC, adjusted for covariates including TNM stage and postoperative chemotherapy in multivariate Cox models. The results in Shanghai cohort were faithfully replicated in Guangzhou cohort. Stromal POSTN expression dose-dependently predicted an unfavorable prognosis of stage III CRC patients with postoperative chemotherapy in both cohorts. POSTN derived from colonic fibroblasts or recombinant POSTN significantly promoted proliferation, anchorage independent growth, invasion, and chemo-resistance of CRC cells; whereas these effects were counteracted via targeting to PI3K/Akt or Wnt/β-catenin signaling pathway. CRC cell RKO-derived factor(s) significantly induced POSTN production in colonic fibroblasts and autocrine POSTN promoted proliferation, migration, and anchorage independent growth of fibroblasts. Conclusively, stromal POSTN is prognostic and predictive for CRC via creating a niche to facilitate cancer progression. Targeting POSTN-induced signaling pathways may be therapeutic options for metastatic or chemoresistant CRC.

Microsatellite alteration and immunohistochemical expression profile of chromosome 9p21 in patients with sporadic renal cell carcinoma following surgical resection

Background

Long-term prognostic significance of loss of heterozygosity on chromosome 9p21 for localized renal cell carcinoma following surgery remains unreported. The study assessed the frequency of deletions of different loci of chromosome 9p along with immunohistochemical profile of proteins in surgically resected renal cancer tissue and correlated this with long-term outcomes.

Methods

DNA was extracted from renal tumours and corresponding normal kidney tissues in prospectively collected samples of 108 patients who underwent surgical resection for clinically localized disease between January 2001 and December 2005, providing a minimum of 9 years follow-up for each participant. After checking quality of DNA, amplified by PCR, loss of heterozygosity (LOH) on chromosome 9p was assessed using 6 microsatellite markers in 77 clear cell carcinoma. Only 5 of the markers showed LOH (D9S1814, D9S916, D9S974, D9S942, and D9S171). Protein expression of p15(INK4b), p16(INK4a), p14(ARF), CAIX, and adipose related protein (ADFP) were demonstrated by immunostaining in normal and cancer tissues. Loss of heterozygosity for microsatellite analysis was correlated with tumour characteristics, recurrence free, cancer specific, and overall survival, including significance of immunohistochemical profile of protein expressions.

Results

The main deletion was found at loci telomeric to CDKN2A region at D9S916. There was a significant correlation between frequency of LOH stage (p = 0.005) and metastases (p = 0.006) suggesting a higher LOH for advanced and aggressive renal cell carcinoma. Most commonly observed LOH in the 3 markers: D9S916, D9S974, and D9S942 were associated with poor survival, and were statistically significant on multivariate analysis. Immunohistochemical expression of p14, p15, and p16 proteins were either low or absent in cancer tissue compared to normal.

Conclusions

Loss of heterozygosity of p921 chromosome is associated with aggressive tumours, and predicts cancer specific or recurrence free survival on long-term follow-up.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-016-2514-8) contains supplementary material, which is available to authorized users.

Significance of chromosome 9p status in renal cell carcinoma: a systematic review and quality of the reported studies

Defining the prognosis of renal cell carcinoma (RCC) using genetic tests is an evolving area. The prognostic significance of 9p status in RCC, although described in the literature, remains underutilised in clinical practice. The study explored the causes of this translational gap. A systematic review on the significance of 9p status in RCC was performed to assess its clinical applicability and impact on clinical decision-making. Medline, Embase, and other electronic searches were made for studies reporting on 9p status in RCC. We collected data on: genetic techniques, pathological parameters, clinical outcomes, and completeness of follow-up assessment. Eleven studies reporting on 1,431 patients using different genetic techniques were included. The most commonly used genetic technique for the assessment of 9p status in RCC was fluorescence in situ hybridization. Combined genomic hybridisation (CGH), microsatellite analysis, karyotyping, and sequencing were other reported techniques. Various thresholds and cut-off values were used for the diagnosis of 9p deletion in different studies. Standardization, interobserver agreement, and consensus on the interpretation of test remained poor. The studies lacked validation and had high risk of bias and poor clinical applicability as assessed by two independent reviewers using a modified quality assessment tool. Further protocol driven studies with standardised methodology including use of appropriate positive and negative controls, assessment of interobserver variations, and evidenced based follow-up protocols are needed to clarify the role of 9p status in predicting oncological outcomes in renal cell cancer.

The regulatory roles of phosphatases in cancer

The relevance of potentially reversible post-translational modifications required for controlling cellular processes in cancer is one of the most thriving arenas of cellular and molecular biology. Any alteration in the balanced equilibrium between kinases and phosphatases may result in development and progression of various diseases, including different types of cancer, though phosphatases are relatively under-studied. Loss of phosphatases such as PTEN (phosphatase and tensin homologue deleted on chromosome 10), a known tumour suppressor, across tumour types lends credence to the development of phosphatidylinositol 3-kinase inhibitors alongside the use of phosphatase expression as a biomarker, though phase 3 trial data are lacking. In this review, we give an updated report on phosphatase dysregulation linked to organ-specific malignancies.

Prognostic significance and molecular mechanism of ATP-binding cassette subfamily C member 4 in resistance to neoadjuvant radiotherapy of locally advanced rectal carcinoma

Background

Mechanism of radioresistance in rectal carcinoma remains largely unknown. We aimed to evaluate the predictive role of ATP-binding cassette subfamily C member 4 (ABCC4) in locally advanced rectal carcinoma and explore possible molecular mechanisms by which ABCC4 confers the resistance to neoadjuvant radiotherapy.

Methods

The expression of ABCC4 and P53 mutant in biopsy tissue specimens from 121 locally advanced rectal carcinoma patients was examined using immunohistochemistry. The factors contributing to 3-year overall survival and disease-free survival were evaluated using the Kaplan-Meier method and Cox proportional hazard model. Lentivirus-mediated small hairpin RNA was applied to inhibit ABCC4 expression in colorectal carcinoma cell line RKO, and investigate the radiosensitivity in xenograft model. Intracellular cyclic adenosine monophosphate concentration and cell cycle distribution following irradiation were detected.

Results

High expression of ABCC4 and p53 mutant in pretreated tumors, poor pathological response, and high final tumor staging were significant factors independently predicted an unfavorable prognosis of locally advanced rectal carcinoma patients after neoadjuvant radiotherapy. Down-regulation of ABCC4 expression significantly enhanced irradiation-induced suppression of tumor growth in xenograft model. Furthermore, down-regulation of ABCC4 expression enhanced intracellular cyclic adenosine monophosphate production and noticeable deficiency of G1-S phase checkpoint in cell cycle following irradiation.

Conclusions

Our study suggests that ABCC4 serves as a novel predictive biomarker that is responsible for the radioresistance and predicts a poor prognosis for locally advanced rectal carcinoma after neoadjuvant radiotherapy.

Genetic variation in the GSTM3 promoter confer risk and prognosis of renal cell carcinoma by reducing gene expression

Background:

Glutathione S-transferase mu 3 (GSTM3) has been proven to be downregulated in renal cell carcinoma (RCC). We aimed to characterise the role of GSTM3 and its genetic predisposition on the occurrence and postoperative prognosis of RCC.

Methods:

The effect of GSTM3 on RCC aggressiveness was examined using transfection and silencing methods. Glutathione S-transferase mu 3 expression in renal tissues was examined by immunohistochemistry. The associations of rs1332018 (A-63C) and rs7483 (V224I) polymorphisms with RCC risk were examined using 400 RCC patients and 802 healthy controls. The factors contributing to postoperative disease-specific survival of RCC patients were evaluated using the Cox proportional hazard model.

Results:

Glutathione S-transferase mu 3 silencing increased the invasion and anchorage-independent growth of RCC cell lines. rs1332018 (AC+CC vs AA), which correlated with low expression of GSTM3 in kidney, was associated with RCC risk (odds ratio, 1.446; 95% confidence interval (CI), 1.111–1.882). rs1332018 variants and low GSTM3 expression significantly predicted unfavourable postoperative survivals of RCC patients (P<0.05). rs1332018 variants independently predicted a poor prognosis (hazard ratio, 2.119; 95% CI, 1.043–4.307).

Conclusion:

Glutathione S-transferase mu 3 may function as a tumour suppressor in RCC. rs1332018 genetic variants predispose the host to downregulating GSTM3 expression in kidney, facilitate carcinogenesis, and predict an unfavourable postoperative prognosis of RCC.

A GWAS-identified susceptibility locus on chromosome 11q13.3 and its putative molecular target for prediction of postoperative prognosis of human renal cell carcinoma

Genome-wide association studies have been used to identify single nucleotide polymorphisms (SNPs) associated with renal cell carcinoma (RCC) in European individuals. The current study aimed to evaluate the correlation between significant SNPs identified in European individuals and the occurrence and postoperative prognosis of RCC in Chinese individuals. A total of 400 cases and 806 controls were involved in the current study. rs4765623, rs7105934, rs7579899 and rs1867785 were genotyped using qPCR, and the expression of cyclin D1 in renal tissue and RCCs was determined via western blotting and immunohistochemistry. The correlation between the SNPs/cyclin D1 expression and overall survival was evaluated using multivariate Cox regression analyses. Of the four SNPs, only rs7105934 was found to significantly correlate with RCC risk in Chinese individuals. The rs7105934 GA + AA genotype was correlated with a reduced risk of RCC with an odds ratio of 0.64 (95% confidence interval [CI], 0.43–0.96), following adjustment for age. This genotype was found to independently predict an improved postoperative prognosis in the multivariate analysis, with a hazard ratio (HR) of 0.12 (95% CI, 0.02–0.93). Expression of cyclin D1, a putative regulated protein of rs7105934, did not vary in adjacent renal tissue and tumors when compared with that of various rs7105934 genotypes. However, cyclin D1 expression in RCCs inversely correlated with advanced tumor stage, and moderate to high expression of cyclin D1 in RCCs independently predicted improved postoperative prognosis, with an HR of 0.13 (95% CI, 0.02–0.96). Observations of the present study indicate that the rs7105934 A allele is associated with reduced risk and improved postoperative prognosis of RCC; however, this effect is unlikely to be caused by cyclin D1 expression.

Protein tyrosine phosphatase variants in human hereditary disorders and disease susceptibilities

Reversible tyrosine phosphorylation of proteins is a key regulatory mechanism to steer normal development and physiological functioning of multicellular organisms. Phosphotyrosine dephosphorylation is exerted by members of the super-family of protein tyrosine phosphatase (PTP) enzymes and many play such essential roles that a wide variety of hereditary disorders and disease susceptibilities in man are caused by PTP alleles. More than two decades of PTP research has resulted in a collection of PTP genetic variants with corresponding consequences at the molecular, cellular and physiological level. Here we present a comprehensive overview of these PTP gene variants that have been linked to disease states in man. Although the findings have direct bearing for disease diagnostics and for research on disease etiology, more work is necessary to translate this into therapies that alleviate the burden of these hereditary disorders and disease susceptibilities in man.

Establishment and characterization of clear cell renal cell carcinoma cell lines with different metastatic potential from Chinese patients

Abstracts