Human skin carcinoma arising from kidney transplant-derived tumor cells

Tumors after kidney transplantation: a population study

One of the main causes of post-transplant-associated morbidity and mortality is cancer. The aims of the project were to study the neoplastic risk within the kidney transplant population and identify the determinants of this risk. A cohort of 462 renal transplant patients from 2010 to 2020 was considered. The expected incidence rates of post-transplant cancer development in the referenced population, the standardized incidence ratios (SIR) taking the Italian population as a comparison, and the absolute risk and the attributable fraction were extrapolated from these cohorts of patients. Kidney transplant recipients had an overall cancer risk of approximately three times that of the local population (SIR 2.8). A significantly increased number of cases were observed for Kaposi's sarcoma (KS) (SIR 195) and hematological cancers (SIR 6.8). In the first 3 years post-transplant, the risk to develop either KS or hematological cancers was four times higher than in the following years; in all cases of KS, the diagnosis was within 2 years from the transplant. Post-transplant immunosuppression represents the cause of 99% of cases of KS and 85% of cases of lymphomas, while only 39% is represented by solid tumors. Data related to the incidence, the percentages attributable to post-transplant immunosuppression, and the time of onset of neoplasms, particularly for KS and hematological tumors could help improve the management for the follow-up in these patients.

Estimated Glomerular Filtration Rate and the Risk of Cancer

BACKGROUND AND OBJECTIVES

Community-based reports regarding eGFR and the risk of cancer are conflicting. We here explore plausible links between kidney function and cancer incidence in a large Scandinavian population-based cohort.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

In the Stockholm Creatinine Measurements project, we quantified the associations of baseline eGFR with the incidence of cancer among 719,033 Swedes ages ≥40 years old with no prior history of cancer. Study outcomes were any type and site-specific cancer incidence rates on the basis of International Classification of Diseases-10 codes over a median follow-up of 5 years. To explore the possibility of detection bias and reverse causation, we divided the follow-up time into different time periods (≤12 and >12 months) and estimated risks for each of these intervals.

RESULTS

In total, 64,319 cases of cancer (affecting 9% of participants) were detected throughout 3,338,226 person-years. The relationship between eGFR and cancer incidence was U shaped. Compared with eGFR of 90-104 ml/min, lower eGFR strata associated with higher cancer risk (adjusted hazard ratio, 1.08; 95% confidence interval, 1.05 to 1.11 for eGFR=30-59 ml/min and adjusted hazard ratio, 1.24; 95% confidence interval, 1.15 to 1.35 for eGFR<30 ml/min). Lower eGFR strata were significantly associated with higher risk of skin, urogenital, prostate, and hematologic cancers. Any cancer risk as well as skin (nonmelanoma) and urogenital cancer risks were significantly elevated throughout follow-up time, but they were higher in the first 12 months postregistration. Associations with hematologic and prostate cancers abrogated after the first 12 months of observation, suggesting the presence of detection bias and/or reverse causation.

CONCLUSIONS

There is a modestly higher cancer risk in individuals with mild to severe CKD driven primarily by skin and urogenital cancers, and this is only partially explained by bias.

Practical applications of DNA genotyping in diagnostic pathology

INTRODUCTION

Among various human tissue identity testing platforms, short tandem repeat (STR) genotyping has emerged as the most powerful and cost-effective method. Beyond forensic applications, tissue identity testing has become increasingly important in modern medical practice, in areas such as diagnostic pathology. Areas covered: A brief overview of various molecular/genetic techniques for identity testing is provided. This includes restriction fragment length polymorphism, single nucleotide polymorphism array and STR genotyping by multiplex PCR. Diagnostic applications of STR genotyping are covered in greater details: genotyping diagnosis of gestational trophoblastic disease, resolving tissue specimen mislabeling or histologic contaminant or 'floaters', bone marrow engraftment/chimerism analysis and interrogation of the primary source of malignancy in patients receiving organ donation. Four clinical cases are then presented to further illustrate these important clinical applications along with discussion of the interpretation, limitations, and pitfalls of STR genotyping. Expert commentary: STR genotyping is currently the most applicable method of identity testing and has extended its role well into the practice of diagnostic pathology with novel and powerful applications beyond forensics.

Targeting Cancer Stem Cells to Overcome Chemoresistance

Cancers are heterogeneous at the cell level, and the mechanisms leading to cancer heterogeneity could be clonal evolution or cancer stem cells. Cancer stem cells are resistant to most anti-cancer treatments and could be preferential targets to reverse this resistance, either targeting stemness pathways or cancer stem cell surface markers. Gold nanoparticles have emerged as innovative tools, particularly for photo-thermal therapy since they can be excited by laser to induce hyperthermia. Gold nanoparticles can be functionalized with antibodies to specifically target cancer stem cells. Preclinical studies using photo-thermal therapy have demonstrated the feasibility of targeting chemo-resistant cancer cells to reverse clinical chemoresistance. Here, we review the data linking cancer stem cells and chemoresistance and discuss the way to target them to reverse resistance. We particularly focus on the use of functionalized gold nanoparticles in the treatment of chemo-resistant metastatic cancers.

Donor-derived stem-cells and epithelial mesenchymal transition in squamous cell carcinoma in transplant recipients

Background

Skin squamous-cell-carcinoma (SCC), is the main complication in long-term kidney-transplant recipients, and it can include donor-derived cells. Preclinical models demonstrated the involvement of epithelial mesenchymal transition (EMT) in the progression of skin SCC, and the role of Snail, an EMT transcription factor, in cancer stem-cell survival and expansion.

Here, we studied stem-cells and EMT expression in SCCs and concomitant actinic keratoses (AK) in kidney-transplant recipients.

Methods

In SCC and AK in 3 female recipients of male kidney-transplants, donor-derived Y chromosome in epidermal stem cells was assessed using combined XY-FISH/CD133 immunostaining, and digital-droplet-PCR on laser-microdissected CD133 expressing epidermal cells.

For EMT study, double immunostainings of CD133 with vimentin or snail and slug, electron microscopy and immunostainings of keratinocytes junctions were performed. Digital droplet PCR was used to check CDH1 (E-cadherin) expression level in laser-microdissected cells co-expressing CD133 and vimentin or snail and slug.

The numbers of Y-chromosome were assessed using digital droplet PCR in laser-microdissected cells co-expressing CD133 and vimentin, or snail and slug, and in CD133 positive cells not expressing any EMT maker.

Results

We identified donor-derived stem-cells in basal layers and invasive areas in all skin SCCs and in concomitant AKs, but not in surrounding normal skin.

The donor-derived stem-cells expressed the EMT markers, vimentin, snail and slug in SCCs but not in AKs. The expression of the EMT transcription factor, SNAI1, was higher in stem-cells when they expressed vimentin. They were located in invasive areas of SCCs. In these areas, the expressions of claudin-1 and desmoglein 1 were reduced or absent, and within the basal layer there were features of basal membrane disappearance.

Donor-derived stem cells were in larger numbers in stem cells co-expressing vimentin or snail and slug than in stem cells not expressing any EMT marker.

Conclusion

We identified here donor-derived stem cells within skin SCC in kidney-transplant recipients. They were located in invasive areas of SCC and had EMT characteristics.

Tracking sub-clonal TP53 mutated tumor cells in human metastatic renal cell carcinoma

Renal Cell Carcinomas (RCCs) are heterogeneous tumors with late acquisition of TP53 abnormalities during their evolution. They harbor TP53 abnormalities in their metastases. We aimed to study TP53 gene alterations in tissue samples from primary and metastatic RCCs in 36 patients followed up over a median of 4.2 years, and in xenografted issued from primary RCCs. In 36 primary RCCs systematically xenografted in mice, and in biopsies of metastases performed whenever possible during patient follow-up, we studied p53-expressing tumor cells and TP53 gene abnormalities.We identified TP53 gene alterations in primary tumors, metastases and xenografts. Quantification of tumors cells with TP53 gene alterations showed a significant increase in the metastases compared to the primary RCCs, and, strikingly, the xenografts were similar to the metastases and not to the primary RCCs from which they were derived.Using laser-microdissection of p53-expressing tumor cells, we identified TP53-mutated tumor cells in the xenografts derived from the primary RCC, and in a lung metastasis later developed in one patient. The mutation enabled us to track back their origin to a minority sub-clone in the primary heterogeneous RCC. Combining in situ and molecular analyses, we demonstrated a clonal expansion in a living patient with metastatic RCC.

Assessment of chimerism in epithelial cancers in transplanted patients

Cancer is now the most severe complication in the long term in transplant recipients. As most solid-organ or hematopoietic stem-cell transplantations are allogeneic, chimerism studies can be performed on cancers occurring in recipients. We summarize here the different methods used to study chimerism in cancers developing in allogeneic-transplant recipients, analyze their respective advantages and report the main results obtained from these studies. Chimerism analyses of cancers in transplant recipients require methods suited to tissue samples. In the case of gender-mismatched transplantation, the XY chromosomes can be explored using fluorescent in situ hybridization on whole-tissue sections or Y-sequence-specific PCR after the laser microdissection of tumor cells. For cancers occurring after gender-matched transplantation, laser microdissection of tumor cells enables studies of microsatellite markers and high-resolution melting analysis of mitochondrial DNA on genes with marked polymorphism, provided these are different in the donor and the recipient. The results of different studies address the cancers that develop in both recipients and in transplants. The presence of chimeric cells in these two types of cancer implies an exchange of progenitor/stem-cells between transplant and recipient, and the plasticity of these progenitor/stem-cells contributes to epithelial cancers. The presence of chimeric cells in concomitant cancers and preneoplastic lesions implies that the oncogenesis of these cancers progresses through a multistep process.

Transplantation: Donor-derived skin cancer in a kidney transplant recipient

Skin carcinomas, triggered by ultraviolet light, commonly develop post-transplantation and are associated with substantial morbidity and mortality. A recent study in kidney transplant recipients has shown that some of these tumours arise from donor-derived cells. This phenomenon is interesting for the study of carcinogenesis, although its effect on clinical practice is unknown.

Donor-associated malignancy in kidney transplant patients

Skin cancer cells with donor genotype have been identified in allogeneic transplant patients; however, the donor contribution to the recipient's epithelial malignancy remains to be established. In this issue of the JCI, Verneuil et al. provide the first evidence for donor contribution to the malignant epithelium of skin squamous cell carcinoma in a kidney transplant recipient. This case report may have important implications for cancer research and clinical care of long-surviving kidney transplant patients.