Bladder cancer: can we move beyond chemotherapy?

EGFR-expression in primary urinary bladder cancer and corresponding metastases and the relation to HER2-expression. On the possibility to target these receptors with radionuclides

Background

There is limited effect of tyrosine kinase inhibitors or “naked” antibodies binding EGFR or HER2 for therapy of metastasized urinary bladder cancer and these methods are therefore not routinely used. Targeting radio-nuclides to the extracellular domain of the receptors is potentially a better possibility.

Methods

EGFR- and HER2-expression was analyzed for primary tumors and corresponding metastases from 72 patients using immunohistochemistry and the internationally recommended HercepTest. Intracellular mutations were not analyzed since only the receptors were considered as targets and intracellular abnormalities should have minor effect on radiation dose.

Results

EGFR was positive in 71% of the primary tumors and 69% of corresponding metastases. Local and distant metastases were EGFR-positive in 75% and 66% of the cases, respectively. The expression frequency of HER2 in related lesions was slightly higher (data from previous study). The EGFR-positive tumors expressed EGFR in metastases in 86% of the cases. The co-expression of EGFR and HER2 was 57% for tumors and 53% for metastases. Only 3% and 10% of the lesions were negative for both receptors in tumors and metastases, respectively. Thus, targeting these receptors with radionuclides might be applied for most patients.

Conclusions

At least one of the EGFR- or HER2-receptors was present in most cases and co-expressed in more than half the cases. It is therefore interesting to deliver radionuclides for whole-body receptor-analysis, dosimetry and therapy. This can hopefully compensate for resistance to other therapies and more patients can hopefully be treated with curative instead of palliative intention.

Transitional cell carcinoma of the bladder: racial and gender disparities in survival (1993 to 2002), stage and grade (1993 to 2007)

PURPOSE

Bladder cancer survival is consistently lower in female and black patients than in male and white patients. We compared trends and differences according to clinical, demographic and facility characteristics by patient race and gender to identify the impact of these characteristics on survival.

MATERIALS AND METHODS

We identified bladder transitional cell carcinoma cases diagnosed in 1993 to 2007 from the National Cancer Data Base. Trends in grade and stage distribution between 1993 and 2007 were analyzed. Survival differences by race and gender were compared using 5-year relative survival and multivariate Cox regression.

RESULTS

There were 310,257 white male, 102,345 white female, 13,313 black male and 7,439 black female patients. Black and female patients had a higher proportion of muscle invasive tumors than white and male patients, and black patients had a larger proportion of higher grade tumors. The incidence of stage 0a and of high grade tumors significantly increased with time. Multivariate analysis showed a significantly lower HR in white females than in white males (HR 0.9) but a significantly higher HR in black males and females (HR 1.2). The higher mortality risk in black males and females was primarily limited to late stage disease (HR 1.3).

CONCLUSIONS

Survival differences by race and gender are partially explained by differences in tumor and demographic characteristics in black males and females, and fully explained by these characteristics in white females. Treatment delays and under treatment due to comorbid conditions, age and other factors may also contribute to these disparities.

Increased antitumor capability of fiber-modified adenoviral vector armed with TRAIL against bladder cancers

Adenoviral vectors are widely used for cancer therapy and show a tumor-suppressing effect. However, bladder cancers are found to be resistant against infection of Ad5-derived adenoviral vector, limiting the application of the existing strategy of gene therapy. Therefore, efforts to develop novel types of adenoviral vector aimed for improving the viral infection and enhancing expression level of tumor-inhibiting transgene is urgently required. We constructed a 5/35 fiber-modified E1A-deleted adenoviral vector armed with TRAIL gene. Its ability to express this gene for inhibition of bladder cancer cell growth was investigated in our work. The results showed that this modification in fiber region facilitates adenoviral infection to bladder cancer, perhaps due to high expression of CD46 on target cell surface. Subsequently, we found an enhanced expression level of TRAIL mediated by 5/35 fiber-modified adenoviral vectors in bladder cancer cells, leading to an increased tumor-inhibiting capability of 5/35 adenoviral vector against bladder cancer cells. Consistently, growth of xenograft tumors in mice was also effectively inhibited by 5/35 fiber-modified vector-mediated gene therapy strategy. The 5/35 fiber-modified adenoviral vector-based gene transfer shows an improved efficacy against bladder cancers. The application of this novel gene therapy vector may benefit the patients in clinical bladder cancer treatment.

A phase I study of personalized peptide vaccination for advanced urothelial carcinoma patients who failed treatment with methotrexate, vinblastine, adriamycin and cisplatin

OBJECTIVE

• To investigate the safety and immune responses of 12 consecutive weeks of once-weekly personalized peptide vaccine (PPV) administration in patients with advanced urothelial carcinoma (UC) for whom therapy with methotrexate, vinblastine, adriamycin and cisplatin (MVAC) has failed.

PATIENTS AND METHODS

• A phase I trial was designed. Ten patients with MVAC-refractory advanced or metastatic UC were treated with weekly personalized peptide vaccine 12 times using positive peptides chosen from 14 and 16 peptides in patients with human leucocyte antigens A24 and A2, respectively. • Peptide-specific cytotoxic T lymphocyte precursor analysis by interferon-γ production and peptide-reactive immunoglobulin G (IgG) using an enzyme-linked immunosorbent assay was monitored during the treatment.

RESULTS

• The peptide vaccination was safe and well tolerated with no major adverse effects. Increased cytotoxic T lymphocyte response and the anti-peptide IgG titre were revealed by the post-vaccination sera in eight patients. • Clinical responses were as follows: one complete response, one partial response, two stable disease and six progressive disease. • Median progression-free survival and overall survival were 3.0 and 8.9 months, respectively. In the four responders, median progression-free survival and overall survival were 21 and 24 months, respectively.

CONCLUSIONS

• This phase I study showed the safety of and boosted immune responses in response to PPV for advanced UC. • The potential efficacy of 12 consecutive weekly vaccinations with PPV in patients with advanced UC merits further investigation based on these findings.