Long-term results of a single-center prospective randomized trial assessing efficacy of a shortened course of adjuvant chemotherapy after radical cystectomy in patients with locally advanced bladder cancer

Introduction

This study assesses the efficacy and tolerability of two cycles of adjuvant chemotherapy (AC) with gemcitabine and cisplatin after radical cystectomy in patients with a high risk of progression of muscle-invasive urothelial bladder cancer as compared to chemotherapy at relapse, in a prospective randomized study.

Material and methods

From 2008 to 2013, all patients after radical cystectomy at our institution for primary or recurrent urothelial bladder cancer with stage pT3-4 and/or pN+ on histopathology and without contraindications to combination cisplatin-based chemotherapy, were randomized either to two cycles of gemcitabine and cisplatin chemotherapy or to follow-up and chemotherapy at the time of relapse. The study endpoints were overall, cancer-specific, and disease-free survival.

Results

The study included 100 patients, of whom 53 received AC and the other 47 were assigned to the control arm. Out of 53 allocated to AC arm, 16 patients did not start chemotherapy or received only one cycle of AC. The median follow-up for patients in the AC and control arms was 88 and 86 months, respectively. In the AC arm the hazard ratio for death from any cause, death from bladder cancer, and disease relapse were 0.70 (95% CI 0.45-1.11; p = 0.13), 0.84 (95% CI 0.50-1.41; p = 0.51), and 0.77 (95% CI 0.46-1.28; p = 0.31), respectively.

Conclusions

Two cycles of AC with gemcitabine and cisplatin in patients with high-risk urothelial bladder cancer after radical cystectomy does not improve overall, cancer-specific, and disease-free survival. Only 53% of patients randomized to AC received the entire planned treatment.

BER gene polymorphisms associated with key molecular events in bladder cancer

AIM

Base excision repair (BER) gene polymorphisms are known to play an independent role in predisposition to developing different cancers as well as to be associated with clinicopathological traits of the disease modifying its clinical outcomes. One of the underlying mechanisms is presumed to include interplay between BER gene polymorphisms and key mutational, epigenetic and chromosomal events in tumor tissues. The present study was aimed at elucidating potential gene-gene interaction and assessing their mutual effects in bladder cancer (BC).

MATERIALS AND METHODS

The earlier obtained data on genotyping patients with verified diagnosis of BC for OGG1 rs1052133 (Ser326Cys) and XRCC1 rs25487 (Arg399Gln) polymorphisms were used for this study. The tumor tissue samples from the same patients were analyzed for mutations, epigenetic variations and losses of heterozygosity in some key genes involved in divergent pathogenic pathways of BC.

RESULTS

It was shown that the OGG1 (326 codon) heterozygous genotype as well as the minor 326Cys allele can intensify a mutational response of the RAS locus in urothelial carcinomas in the total cohort of patients simultaneously decreasing the mutation rates in the PIK3CA locus in smokers. The XRCC1 (399 codon) heterozygous genotype as well as the minor 399Gln allele reduced the frequency of LOH in the PTEN and TNKS genes, but did not affect the mutational variability in any locus tested. Both polymorphisms influenced the methylation status, carriers of OGG1 326Ser/Cys or Ser/Cys+Cys/Cys genotypes demonstrating increased frequency of methylated RUNX3 and ISL1 genes whereas the similar effect of XRCC1 polymorphism concerning methylation of p16 and TIMP3 genes. When dividing the total cohort into groups based on the extent of tumor spread, the observed associations were characteristic of non-muscle invasive BC.

CONCLUSION

The BER gene polymorphisms contributed to modification of key molecular events in urothelial carcinomas. Their mutual effects mainly manifested in non-muscle invasive BC. The underlying mechanisms as well as possible clinical outcomes need to be further explored to propose novel prognostic biomarkers for BC.

FGFR3 and TP53 mutations in a prospective cohort of Belarusian bladder cancer patients

AIM

The aim of this study was to determine the frequencies of FGFR3 and TP53 mutations in a prospective cohort of 150 bladder cancer patients and to assess the relationship between their mutational status and clinicopathological variables.

MATERIALS AND METHODS

The FGFR3 and TP53 mutations were detected by the SNaPshot method and PCR-single-strand conformational polymorphism analysis followed by DNA sequencing.

RESULTS

The activating FGFR3 mutations were found in 71 (47.3%) whereas TP53 mutations were observed in 31 (20.7%) urothelial carcinomas. FGFR3-mutant tumors significantly correlated with lower tumor stage and grade, papillary form of bladder cancer and the absence of metastases while TP53-mutant tumors were strongly associated with higher tumor stage and grade as well as the presence of metastasis. We also found significant inverse correlation between FGFR3 mutations and TP53 alterations in urothelial carcinomas (p=0.03). Four possible genotypes were observed in the whole studied cohort, namely FGFR3mut/TP53wt (41.3%), FGFR3wt/TP53wt (38%), FGFR3wt/TP53mut (14.7%), and FGFR3mut/TP53mut (6%). Tumors with FGFR3wt/TP53wt genotype comprised the subgroup, in which all stages and grades were equally distributed.

CONCLUSIONS

Our findings confirm the alternative role of FGFR3 and TP53 mutations in the development of bladder cancer. Together these two genetic markers are attributed to 62% of the tumors studied. Tumors with both wild type genes included urothelial carcinomas of all stages and grades and may develop through another genetic pathway. To elucidate complete molecular profile of bladder tumors further additional studies are needed.

Intercellular complement C3 binding in normal skin of patients without pemphigus

We report here direct immunofluorescence studies of normal skin biopsies that exhibited only complement C3 staining in intercellular areas of epithelium with a view toward evaluating the significance of such findings. During a 5-year period, 11,000 skin biopsy specimens were examined for in vivo binding of immunoglobulins, fibrin, and complement C3 by means of defined direct immunofluorescence methods. Four of ten patients demonstrating intercellular C3 deposits alone had drug-related reactions or erythema multiforme, and four were subsequently shown to have a connective tissue disease. Pemphigus was ruled out in all ten cases in these retrospective studies. These observations indicate that the finding of intercellular C3 deposits in the absence of IgG in normal skin is not a sign of pemphigus but, rather, a sign either of an unusual type of drug reaction or, possibly, of some connective tissue disease. However, the finding of intercellular C3 plus IgG (with or without other immunoglobulins) is a sign of pemphigus. The mechanism of C3 deposition without immunoglobulins is not clear.

Evaluation of methods for detection of anticentromere antibodies and other antinuclear antibodies

Our immunologic studies of twenty-five patients with acrosclerosis with severe acral involvement, twenty-seven patients with most or all of the signs of CREST syndrome, twenty-two patients with systemic lupus erythematosus as positive controls, and ninety-one blood donors as negative controls centered on an evaluation of eight antigenic substrates, including four types of human cells for the detection of anticentromere antibodies (ACA) and other antinuclear antibodies (ANA). The ACA, which occurred only among the patients with most or all of the signs of CREST syndrome, could be detected reliably on human cell lines HEp-2 and KB but not on a mouse cell line or on the three types of tissue sections examined. Comparisons of human HEp-2 and KB cell lines from four sources indicated that HEp-2 cells are the best of the substrates tested for detection of ACA. Since rodent tissue sections give negative reactions with ACA, they are indicated for confirmation. In general, results varied with the type and source of antigen used. Thus ANA findings need to be expressed not only in terms of the titers of the antibodies and the pattern(s) of their reactions but also in terms of the type of antigen or substrate used, its source, and the diagnostic significance of findings in the given test system.

Effect of erythrocytes treated with enterobacterial common antigen on experimental Salmonella typhimurium infection of mice

The immunogenicity of enterobacterial common antigen (CA)-treated horse or mouse erythrocytes was determined in Swiss white albino mice by comparing survival rates with control mice, immunized with P. aeruginosa fraction-treated RBC and challenged in parallel with 10 LD50 S. typhimurium. The administration of small amounts of CA on horse, but not mouse, RBC significantly delayed mortality; protection was only marginally less than that evoked with 12-fold larger amounts of CA in the absence of RBC. Survival in infected animals was transient; independent of immunogen or control preparation employed, all mice were dead by day 15 after challenge.

Cross-reactivity between organ extracts of gnotobiotic mice and enterobacterial common antigen

Organs of gnotobiotic mice were assessed for an Ag (CRA) which cross-reacts with common enterobacterial Ag(CA). To this end, extracts of homogenates of spleens, livers, paired kidneys and colons were examined for their capacities to engender humoral and cellular events in rabbits. The immjnogenicity of CRA in the rabbit cannot be predicted on the basis of CA hemagglutinin-inhibition studies alone. According to this parameter, CRA was present in mouse spleens, livers and paired kidneys but absent in colons. However, the identical preparations, including colons, primed rabbits to engender specific CA hemaglutinins after a single administration of enterobacterial CA. Also, spleens of these same rabbits were colonized with rosette-forming cells against sheep red blood cells treated with various enterobacterial sources of CA. These findings may account, in part, for the apparent refractiveness or equivocal response mice have to administered CA and infectious challenge.

Immunologic mimicry between mouse tissue and enterobacterial common antigen

Organs of Swiss white albino and C57BL/6Ha mice were assessed for an antigen (CRA) which cross-reacts with common enterobacterial antigen (CA). To this end, supernatant fluids (HKS) and ethanol-soluble fractions (ES) of heated homogenates of spleens, kidneys, and livers were examined for their capacities to react with CA hemagglutinins and to engender humoral and cellular events in the rabbit. The immunogenicity of CRA in the rabbit can not be predicted on the basis of CA hemagglutinin neutralization studies alone; although CRA was identified in the liver extracts of both mouse strains, according to this parameter, only the liver fraction of Swiss white albino mice elicited significant numbers of rosette-forming cells (RFC) in the spleens of rabbits. Also, kidney fractions, which primed the rabbits for booster with CA, were less effective in stimulating RFC in the spleens failed to inhibit CA hemagglutination and did not prime rabbits for a CA hemagglutinin response, these same preparations clearly evoked RFC in rabbit spleens. Thus, the antigenicity and immunogenicity of CRA in target organs of mice reflect the mouse strain, extraction procedure, and testing method employed.