HLA antigen expression in enteropathy associated T cell lymphoma

A viral map of gastrointestinal cancers

Cancers of the gastrointestinal tract (GIT) are expected to account for approximately 20% of all cancers in 2017. Apart from their high incidence, GIT cancers show high mortality rates, placing these malignancies among the most prominent public health issues of our time. Cancers of the GIT are the result of a complex interplay between host genetic factors and environmental factors and frequently arise in the context of a continued active inflammatory response. Several tumor viruses are able to elicit such chronic inflammatory responses. In fact, several viruses have an impact on GIT tumor initiation and progression, as well as on patients' response to therapy and prognosis, through direct and indirect mechanisms. In this review, we have gathered information on different viruses' rates of infection, viral-driven specific carcinogenesis mechanisms and viral-related impact on the prognosis of cancers of the GIT (specifically in organs that have an interface with the environment - esophagus, stomach, intestines and anus). Overall, while some viral infections show a strong causal relation with specific gastrointestinal cancers, these represent a relatively small fraction of GIT malignancies. Other types of cancer, like Esophageal Squamous Cell Carcinoma, require further studies to confirm the carcinogenic role of some viral agents.

HLA-DR overexpression in tubules of renal allografts during early and late renal allograft injuries

OBJECTIVES

We sought to discover which types of injuries were related to human leukocyte antigen DR expression in acute rejection and late chronic injury in renal allografts.

MATERIALS AND METHODS

Ninety-two recipients were separated into the early acute rejection group, the late monocyte infiltration group, and the late chronic injury group. Ten subjects with acute cellular rejection received a repeat biopsy. All samples were stained with CD4, CD8, CD20, CD68, and human leukocyte antigen DR by immunochemical staining. Levels of these markers were compared among the subgroups of each group.

RESULTS

Human leukocyte antigen DR expression was greater in the early C4d-negative acute rejection group than it was in the early C4d-positive acute rejection group. Human leukocyte antigen DR expression was greater during acute rejection than that was on a repeat biopsy. Human leukocyte antigen DR expression was accord with the infiltration of monocyte infiltration in the acute cellular rejection group. Human leukocyte antigen DR expression was greater during late acute rejection than it was in BK virus nephropathy, which was not in accord with monocyte infiltration. Human leukocyte antigen DR expression was greater during chronic rejection than it was in IgAN, BK virus nephropathy, and TA/IF groups, and even in tubular atrophy.

CONCLUSIONS

Human leukocyte antigen DR expression in renal tubular cells was associated with early acute cellular rejection and was in accord with monocyte infiltration. Human leukocyte antigen DR expression in renal tubular cells during the late phase (especially in tubular atrophy) was a marker of chronic rejection, but was not in accord with monocyte infiltration in renal allografts.

Decreased HLA-A expression in prostate cancer is associated with normal allele dosage in the majority of cases

A comparison has been made of the phenotypic expression of MHC class I antigens with the corresponding HLA-A genotype in 15 cases of benign prostatic hyperplasia (BPH) and 34 cases of primary locally invasive prostatic carcinoma. Expression of class 1 protein, detected by immunocytochemistry, was partially or completely lost in approximately 90% of the tumours examined. Comparative genomic analysis of the beta2 microglobulin (beta2m) gene and 15 individual HLA-A haplotypes using a polymerase chain reaction (PCR)-based method demonstrated abnormal gene dosage in the minority of cases: homozygous deletion of the beta2m locus was detected in one case and HLA-A allele in two cases (HLA-A1 and HLA-A2, respectively), representing approximately 8% of the population studied. This first comparative study of gene dosage and expression of class 1 protein reported for prostate cancer reveals that deletion is not the cause of the partial or complete loss seen in the majority of cases. This raises the possibility, in the future, for novel selective immunomodulatory therapeutic strategies which stimulate a clinically significant re-expression of class 1 protein and associated cytotoxic T-cell response.

Aggressive NK cell lymphoma preceded by a ten year history of neutropenia associated with large granular lymphocyte lymphocytosis

We report a case of aggressive natural killer (NK) cell lymphoma in an 82 year old man who first presented 10 years earlier with neutropenia in association with a large granular lymphocyte (LGL) lymphocytosis. The diagnosis of NK cell lymphoma was made on the basis of morphological and immunological characteristics (CD3-CD56+) found on skin biopsy of one of multiple skin nodules which subsequently developed in association with splenomegaly, thrombocytopenia and continuing neutropenia. In addition there was BM infiltration and a cytogenetic abnormality [add(6)(p25)] was detected. Combination chemotherapy led to an initial clinical response but a relapse occurred shortly afterwards and the patient died 8 months later from infection whilst neutropenic following re-introduction of chemotherapy. Previously reported cases of aggressive NK cell lymphoma have shown a young male predominance with a rapidly progressive clinical course and without evidence of a preceding chronic phase of LGL lymphocytosis and neutropenia.