Heikki Helin

Evaluation of cell proliferation in breast carcinoma. Comparison of Ki-67 immunohistochemical study, DNA flow cytometric analysis, and mitotic count

Growth kinetics of 102 breast carcinomas were studied by immunohistochemical analysis with the monoclonal antibody Ki‐67, which reacts with a nuclear antigen in proliferating cells. The results were correlated with ploidy and S‐phase fraction (SPF) analyzed by DNA flow cytometric study and with mitotic count analyzed by light microscopic study. The proportion of Ki‐67‐positive cells (Ki‐67 score) in breast carcinomas varied from 0.6% to 80% (median, 6.3%). Ki‐67 scores were significantly higher in the DNA aneuploid than in the DNA diploid tumors. Ki‐67 scores correlated significantly with tumor SPF in DNA aneuploid tumors. In DNA diploid tumors SPF showed no correlation with Ki‐67 score. High Ki‐67 scores were associated with high mitotic counts (P < 0.0001) and histologic grade (P < 0.0001). Nuclear pleomorphism, tubule formation, or lymph node status were not correlated with Ki‐67 score. In conclusion, Ki‐67 immunostaining correlates with other measures of cell proliferation (SPF, mitotic count) supporting its clinical significance.

Immunohistochemical determination of estrogen and progesterone receptors in human breast carcinoma. Correlation with histopathology and dna flow cytometry

Human breast carcinomas (n = 232) were evaluated for estrogen and progesterone receptors (ER, PR) by immunohistochemical study and by cytosol steroid‐binding assay (n = 185). The staining was scored (histoscore) by estimates of relative nuclear staining intensity and the percentage of positively stained carcinoma cells. Of the invasive ductal carcinomas 72% were ER‐positive and 55% were PR‐positive. The invasive lobular, intraductal, tubular, and mucinous carcinomas were the most frequent ER‐positive tumor types, whereas comedo and medullary carcinomas only rarely contained ER. Progesterone receptor was most frequently present in intraductal, tubular, and mucinous carcinomas. Better differentiated tumors with lower histologic grade were significantly associated with high prevalence of immunohistochemically determined ER and PR (P < 0.0001). Proliferative cell fraction, determined by DNA flow cytometric study (n = 63), was inversely related to ER (P = 0.03) and PR (P = 0.05) status. Aneuploidy was independent of ER or PR content.

Clinicopathologic Correlations in a Series of 143 Patients with IgA Glomerulonephritis

In an unselected series of patients with IgA glomerulonephritis, old age, high blood pressure, and high urinary protein excretion at the time of renal biopsy were found to correlate with impaired renal function, whereas sex, estimated duration of the disease, or high serum IgA levels did not. The following clinical features were favorable prognostic signs: asymptomatic proteinuria, macroscopic hematuria, and isolated microscopic hematuria. The degree of diffuse mesangial alteration and the presence of segmental glomerular lesions correlated clearly with the subsequent clinical outcome. Vascular lesions, i.e. arteriosclerosis and renal vascular deposition of C3, were most often present in patients with severe glomerulopathy. The presence of electron-dense deposits in glomerular capillary walls was also an unfavorable prognostic finding. Renal biopsy findings of interstitial infiltrates of inflammatory cells and IgA distributed along glomerular capillary walls were usually associated with extrarenal manifestations of the disease.

IgM-associated glomerulonephritis.

In a series of 374 renal biopsy specimens, 26 from patients with primary glomerulonephritis showed IgM as the main glomerular immunofluorescence finding. By light microscopy 17 of these specimens showed mild mesangial hypercellularity and 9 were normal. Small mesangial electron-dense deposits were seen in 8 specimens. Of the 26 patients, 10 had proteinuria, 6 had the nephrotic syndrome, 6 had hematuria and 4 had both proteinuria and hematuria. The mean serum IgM level was significantly higher in the patients than in healthy controls. Circulating immune complexes were detected by three methods in 39% of the patients.

Clinical Follow-Up of 54 Patients with IgM-Nephropathy

The clinical course of mesangial glomerulopathy with IgM deposits (IgM-nephropathy) was studied in 54 patients. The initial manifestations of the disease were nephrotic syndrome in 18, proteinuria in 21, proteinuria together with hematuria in 4 and isolated hematuria in 11 patients. The nephrotic syndrome was steroid-responsive in 60% of cases and of these 80% were steroid-dependent. During a 5-year postbiopsy follow-up 3 patients went into terminal uremia and in 6 more patients a milder renal insufficiency was observed. Three patients were rebiopsied and in 2 of these the second biopsy specimen disclosed typical focal and segmental glomerulosclerosis. Hematuria was a favorable sign, as no patient with hematuria showed progressive impairment of renal function. The prevalence of hypertension in the whole material was 37%. At close of follow-up 35% of all patients were in clinical remission. It is suggested that IgM-nephropathy associated with abundant proteinuria or the nephrotic syndrome represents a distinct disorder from that associated with hematuria. While the nephrotic type often manifested itself with a morphologic change and a tendency to develop renal insufficiency, the hematuric type showed female predominance, a high tendency to spontaneous clinical remission and a favorable clinical course.

Immunoelectron-microscopic localization of a proliferation-associated antigen Ki-67 in MCF-7 cells

SummaryImmunocytochemistry using the monoclonal antibody Ki-67 is a commonly used method to assess proliferative activity of malignant tumours. Ki-67 reacts with proliferating cells with an antigen, whose structure, function and exact locations are unknown. We studed the subcellular location of Ki-67 in MCF-7 cells using immunoelectron microscopy. In the interphase cells, Ki-67 immunoreactivity was localized in the nucleolus, mainly in the nucleolar cortex. In particular areas of the granular component of the nucleolus were strongly stained. Weak spot-like nucleoplasmic immunostaining was also seen outside the nucleolus. During prophase Ki-67 antigen was localized on the surfaces of the condensed chromatin and during metaphase on the surface of the chromosomes. After cell division and prior to formation of new nucleoli, Ki-67 immunoreactivity was located in the nucleoplasm. Quantification of Ki-67 immunofluorescence signal by flow cytometry revealed highest Ki-67 levels in mitotic cells. The localtion of Ki-67 is very similar to certain recently described proteins of nucleolar preribosomes suggesting that Ki-67 may also be a component of the preribosomes.

Mild Mesangial Glomerulopathy – A Frequent Finding in Rheumatoid Arthritis Patients with Hematuria or Proteinuria

Renal biopsy specimens from 39 patients with rheumatoid arthritis and clinical signs of renal disease disclosed a mild mesangial glomerulopathy in more than 1 in 4 cases. Almost all patients had deposits of immunoglobulin and complement in the mesangial lesions. This type of glomerulopathy was the most common cause of hematuria and was also frequently encountered in proteinuric patients. Clinically it was not possible to distinguish between mesangial and membranous nephropathy.

Renal biopsy in acute renal failure.

Renal biopsies were performed on 91 out of 99 patients with acute intrinsic renal failure. In all these 91 cases a clinical diagnosis was suggested by an experienced nephrologist unaware of the renal biopsy findings. Most diagnoses agreed with the histopathological findings, but there were important exceptions. On clinical grounds, acute tubulointerstitial renal disease was diagnosed correctly in 77% and acute glomerulonephritis in 56%. In 15% of the patients the clinical data did not permit any certain diagnostic suggestion. In about 20% the biopsy finding definitely influenced the choice of medical treatment. In those 15 patients who needed dialysis treatment, the biopsy findings helped in determining whether this need was temporary or permanent. Our results show that renal biopsy is valuable in settling the diagnosis, in determining the prognosis, and in planning the treatment of acute intrinsic renal failure.

Mesangial Glomerulopathy in Rheumatoid Arthritis Patients

23 patients (16 women, 7 men) with rheumatoid arthritis (RA) and renal biopsy-proven mesangial glomerulopathy (MGP) were followed for 4–117 months (median 42) in order to evaluate the clinical course

In vivo binding of immunoglobulin and complement to elastic structures in urinary bladder vascular walls in interstitial cystitis: Demonstration by immunoelectron microscopy

An ultrastructural immunoperoxidase staining technique was used to identify and localize immune deposits in the urinary bladder vessel walls of patients with interstitial cystitis. Deposition of immunoglobulin together with the C3 component of complement was found in the subendothelial space and in endothelial basement membranes. More peripherally, deposits were often found associated with elastic fibers between smooth muscle cells. In these fibers the staining was confined to the microfibrillar coat. The findings suggest that elastic microfibrils act as target sites for the immunologic reaction occurring in vivo. Following binding of autoantibodies to antigens in bladder mucosa, activation of complement could be involved in the production of tissue injury and in the chronic self-perpetuating inflammation typical of this disease.