Cytoplasmic localization of p63 is associated with poor patient survival in lung adenocarcinoma.

AIMS: To determine the significance of p63 protein expression in the development and progression of lung adenocarcinoma. METHODS AND RESULTS: The expression of p63 was immunohistochemically investigated in 92 cases of lung adenocarcinoma with a maximum diameter of 30 mm or less. p63 expression was observed not only in the nuclei (46/92 cases, 50%), but also in the cytoplasm of neoplastic cells (47/92, 51%). Nuclear localization of p63 was correlated with nuclear accumulation of p53 (P=0.0120), whereas the presence of nuclear p63 had no apparent effect on patient survival. Cytoplasmic localization of p63 was found to be correlated with shorter survival periods by univariate and multivariate analyses (P=0.0486 and P=0.0488, respectively) and the relation was independent of clinicopathological factors. Cytoplasmic localization of p63 was further confirmed by immunoblots of the cytoplasmic fraction of HLC-1, a lung adenocarcinoma cell line which predominately expressed DeltaNp63alpha transcript relative to TAp63 transcript by quantitative reverse transcriptase-polymerase chain reaction. CONCLUSIONS: Cytoplasmic expression of p63 is an adverse prognostic factor in patients with adenocarcinoma of the lung.

SUMOylation substrates in neuronal intranuclear inclusion disease.

Neuronal intranuclear inclusion disease (NIID) is a rare neurodegenerative disorder characterized pathologically by the presence of ubiquitinated intranuclear inclusions (NII) in neuronal cells. We demonstrate that NIIs in both sporadic and familial NIID contained the small ubiquitin modifier-1 (SUMO-1) and the SUMOylation substrates promyelocytic leukaemia protein (PML) and histone deacetylase 4 (HDAC4). Both PML and SUMO-1 are major components of nuclear bodies (NBs), suggesting that the NIIs in NIID, as well as the intranuclear inclusions in polyglutamine diseases, might derive from these intranuclear functional domains that serve as sites for ubiquitin-related protein degradation. HDAC4 was also a major component of the NIIs. HDACs are transcriptional corepressors that regulate histone remodelling, and NBs are thought to be sites at which the level of histone acetylation is controlled. The presence of PML, SUMO-1 and HDAC4 in NIIs suggests that transcriptional activity regulated by histone acetylation might contribute to the disease process in NIID. In addition, we showed that another SUMOylation substrate, RanGAP1 is associated with NIIs only in the familial NIID patient. This might be explained by different pathogenetic mechanisms underlying subcategories of NIID, which is very heterogeneous.

IgG4-related sclerosing disease incorporating sclerosing pancreatitis, cholangitis, sialadenitis and retroperitoneal fibrosis with lymphadenopathy.

BACKGROUND AND AIMS: Autoimmune pancreatitis is usually associated with elevated serum IgG4 concentrations, and sometimes with sclerosing cholangitis and Sjögren's syndrome. This study aimed to elucidate the proposed entity of IgG4-related sclerosing disease. METHODS: Subjects were patients with autoimmune pancreatitis (n = 26), sclerosing sialadenitis (n = 5), chronic alcoholic pancreatitis (n = 20), sialolithiasis (n = 34), Sjögren's syndrome (n = 50), and primary sclerosing cholangitis (n = 3). Sections of various organs and tissues of these patients were examined immunohistochemically using antibodies to CD4-T, CD8-T, and CD20-B cell subsets and IgG4, and serum IgG4 concentrations were measured. RESULTS: Patients with autoimmune pancreatitis were associated with sclerosing cholangitis (n = 23), sclerosing sialadenitis (n = 2), retroperitoneal fibrosis (n = 2), and abdominal (n = 5) and cervical (n = 4) lymphadenopathy. They demonstrated infiltrations of more abundant IgG4-positive plasma cells in the pancreas, peripancreatic retroperitoneal tissues, extrahepatic bile duct, gallbladder, stomach, minor salivary gland, and abdominal lymph nodes compared with those of other diseases (p < 0.01). Such infiltrations were also observed in the minor salivary gland and submandibular gland of patients with sclerosing sialadenitis (p < 0.01). Serum IgG4 concentrations were significantly elevated in patients with autoimmune pancreatitis and sclerosing sialadenitis (p < 0.01). CONCLUSION: We propose a new clinicopathological entity of IgG4-related sclerosing disease incorporating sclerosing pancreatitis, cholangitis, sialadenitis and retroperitoneal fibrosis with lymphadenopathy.

Gastrointestinal findings in patients with autoimmune pancreatitis.

BACKGROUND AND STUDY AIMS: Autoimmune pancreatitis (AIP) is a condition that has been proposed as a clinical entity only fairly recently. Its pathogenesis involves autoimmune mechanisms. Although the radiological findings in patients with AIP have been well evaluated, few studies have focused on the gastrointestinal findings in these patients. The aim of this study was to explore the endoscopic and histological findings in the gastrointestinal tract in patients with autoimmune pancreatitis. PATIENTS AND METHODS: The endoscopic findings in the stomach (n = 10), the duodenum (n = 18), the major duodenal papilla (n = 18), and the colon (n = 5) in 24 patients with AIP were reviewed. These were compared with the results of histological examination of gastric mucosa (n = 13), duodenal mucosa (n = 9), the major duodenal papilla (n = 3), and colonic mucosa (n = 3) in these patients. All these specimens were subjected to immunohistochemical study using anti-IgG4 antibody. RESULTS: Foci of slightly pale, thickened mucosa with loss of visible vascular pattern were observed in the stomach in four patients and in the colon in two patients on endoscopy. Slight or moderate swelling of the major duodenal papilla was detected in five patients. Slight to moderate lymphoplasmacytic infiltration was observed in the lamina propria of the gastric and colonic mucosa, and of the major duodenal papilla. Heavy infiltration with IgG4-positive plasma cells (>10 cells per high-power field) was observed in the lamina propria of the stomach in seven patients, of the colon in two patients, and of the major duodenal papilla in three patients; this was not observed in the control patients, who had other diseases. CONCLUSIONS: Although there were no specific endoscopic findings in the stomach or colon in patients with autoimmune pancreatitis, foci of slightly pale, thickened mucosa with loss of visible vascular pattern were observed in some cases. This indistinct change seen on endoscopy appears to be due to heavy infiltration with IgG4-positive plasma cells, associated with CD4- or CD8-positive T lymphocytes, in the lamina propria of the gastric or colonic mucosa.

Association between intratumoral free and total VEGF, soluble VEGFR-1, VEGFR-2 and prognosis in breast cancer.

Vascular endothelial growth factor (VEGF) receptors consist of three cell-membrane type receptors (VEGFR-1, VEGFR-2 and VEGFR-3), and soluble form of VEGFR-1 (sVEGFR-1), an intrinsic negative counterpart of the VEGF. In this study, we measured intratumoral protein levels of free and total VEGF, VEGFR-2 and sVEGFR-1 from 202 primary breast cancer tissues and examined their prognostic values. A significant inverse correlation was found between free or total VEGF and oestrogen receptor (ER) status (P=0.042 and 0.032, respectively). A univariate analysis showed that low sVEGFR-1 and high total VEGF were significantly associated with poor prognosis in disease-free survival (DFS) and overall survival (OS). The ratio of sVEGFR-1 to total VEGF was a strong prognostic indicator (DFS: P=0.008; OS: P=0.0002). A multivariate analysis confirmed the independent prognostic values of total VEGF and the ratio of sVEGFR-1 to total VEGF. In subgroup analysis, total VEGF was a significant prognostic indicator for ER-positive tumours but not for ER-negative tumours, whereas sVEGFR-1 was significant for ER-negative tumours but not for ER-positive tumours. In conclusion, the intratumoral sVEGFR-1 level, VEGF level and the ratio of sVEGFR-1 to total VEGF are potent prognostic indicators of primary breast cancer, and might be relevant to ER status.

Modulation of thymidine phosphorylase by neoadjuvant chemotherapy in primary breast cancer.

The combination effect of docetaxel and capecitabine on tumour response rate and survival was demonstrated recently in metastatic breast cancer patients. This combination was based on an experimental hypothesis that taxane can increase tumour sensitivity to the effect of capecitabine through the upregulation of thymidine phosphorylase (TP), which is responsible for the metabolism of 5-fluorouracil (5-FU) and its derivatives, including capecitabine. To examine the alteration in TP expression before and after neoadjuvant chemotherapy, 92 patients with primary breast cancer (T2-4N0-1M0) were enrolled in this study; 14 were treated with adriamycin and cyclophosphamide (AC) or epirubicin and cyclophosphamide (EC); 58 with 5-FU, adriamycin, and cyclophosphamide (FAC) or 5-FU, epirubicin, and cyclophosphamide (FEC); and 20 with FEC followed by docetaxel/taxotere (TXT-containing regimen). Thymidine phosphorylase upregulation was seen in 54.4% and 32.6% of patients in tumour cells and stromal cells, respectively. Increases in TP expression were found only in the AC/EC and TXT-containing regimen groups. In conclusion, it was strongly suggested that unlike 5-FU-containing regimens, the taxane and AC combination therapies upregulate TP expression in primary breast cancer. Thymidine phosphorylase upregulation by several anticancer drugs implies the importance of individualised strategies for sensitisation of tumour tissues to 5-FU and its derivatives.

Clinical features and treatment of hematopoietic stem cell transplantation-associated gastric antral vascular ectasia.

Gastric antral vascular ectasia (GAVE) may occur after hematopoietic stem cell transplantation (HSCT) and cause severe and prolonged gastric bleeding. The underlying pathology of transplant-associated GAVE (HSCT-GAVE) is poorly understood and an effective therapeutic strategy has not been established yet. We retrospectively reviewed the medical records of 230 consecutive allogeneic transplant recipients in our institution between January 1997 and June 2002. We identified five patients who developed HSCT-GAVE (2.2%). Four patients had bleeding from HSCT-GAVE and one patient had HSCT-GAVE discovered incidentally. The clinical features of these patients were similar in that they all received conditioning treatment with busulfan and had history of thrombotic microangiopathy. Furthermore, treatment with a beta-blocker apparently improved the outcome of HSCT-GAVE in three patients.

Attenuated nuclear shrinkage in neurones with nuclear inclusions of SCA1 brains.

BACKGROUND: Spinocerebellar ataxia type 1 (SCA1) is one of the autosomal dominant neurodegenerative disorders commonly linked to pathological expansion of the CAG repeat of the relevant gene. Nuclear inclusions and neurodegeneration are both triggered by this pathological expansion of the CAG/polyglutamine repeat on ataxin-1, but it remains to be determined whether or not nuclear inclusion formation is associated with accelerated neurodegeneration. OBJECTIVE: To examine the influence of nuclear inclusions on nuclear size and deformity in human brains from patients suffering from SCA1. MATERIAL: Pontine sections of brains obtained at necropsy from seven patients with SCA1 and five controls. METHODS: The size and deformity of each neuronal nucleus was quantified. Nuclei with and without inclusions were examined separately to assess the possible influence of nuclear inclusions on neurodegeneration. RESULTS: Nuclear shrinkage and deformity were more marked in SCA1 brains than in controls. This shrinkage was attenuated in neurones containing nuclear inclusions. CONCLUSIONS: The existence of nuclear inclusions in SCA1 is presumably linked to a mechanism that attenuates rather than accelerates nuclear shrinkage. This in vivo finding may provide a clue to constructing a rational therapeutic strategy for combating neurodegeneration associated with nuclear inclusions.

Close relationship between autoimmune pancreatitis and multifocal fibrosclerosis.

BACKGROUND: Autoimmune pancreatitis is a unique clinical entity proposed recently, and is sometimes associated with inflammation of other organs. AIMS: To examine the pathophysiology of the pancreas and other organs in patients with autoimmune pancreatitis. PATIENTS AND METHODS: We evaluated clinicopathological findings in six resected and one autopsied patient with autoimmune pancreatitis. The pancreas, peripancreatic tissue, bile duct, and gall bladder were examined histologically and immunohistochemically. Biopsied salivary gland and cervical lymph node of one patient were also examined. We also performed similar immunohistochemical examinations in pancreatectomy specimens from 10 patients with alcoholic chronic pancreatitis and biopsied salivary glands from five patients with Sjögren's syndrome. RESULTS: Stenosis of the extrahepatic bile duct was detected in all patients. Histological findings were characterised by diffuse lymphoplasmacytic infiltration with marked interstitial fibrosis and acinar atrophy, obliterated phlebitis of the pancreatic veins, and involvement of the portal vein. Immunohistochemically, diffusely infiltrating cells consisted predominantly of CD4 or CD8 positive T lymphocytes and IgG4 positive plasma cells. Similar inflammatory processes also involved the peripancreatic tissue, extrahepatic bile duct, gall bladder, and salivary gland. Lymph nodes were swollen with infiltration of IgG4 positive plasma cells. None of these findings was seen in alcoholic chronic pancreatitis or Sjögren's syndrome. CONCLUSIONS: The development of the specific inflammations in extensive organs as well as the pancreas in patients with autoimmune pancreatitis strongly suggests a close relationship between autoimmune pancreatitis and multifocal fibrosclerosis.

Primary osteosarcoma arising in the colon: report of a case.

A 53-year-old female presented with abdominal pain, and computed tomography scan revealed a small, calcified lesion in the wall of the transverse colon. The symptoms later disappeared spontaneously, and she remained in good health. However, four years later, she developed lancinating abdominal pain and was admitted to our hospital. A large tumor with calcification was found in the left upper abdominal cavity. Curative resection of the tumor was performed, and the histology was compatible with extraskeletal osteosarcoma. We speculated that the tumor originated from the colonic wall, because a small calcification was observed in the wall of the transverse colon four years before surgery. To the best of our knowledge, this is the first report of primary colonic osteosarcoma.

Pulmonary gangliocytic paraganglioma: case report and comparative immunohistochemical study of related neuroendocrine neoplasms.

The authors report a case of gangliocytic paraganglioma of the lung, which has not yet been described in a pulmonary neoplasm. A 75-year-old man underwent right middle and lower lobe lobectomy. A slightly yellowish mass was located at the bifurcation between the lower and middle lobe bronchus, protruding into the truncus intermedius. The neoplastic cells were composed of three cellular elements: uniform endocrine cells in a Zellballen arrangement, large ganglion-like cells within the nests of endocrine cells, and spindle-shaped cells arranged in streams to surround the nests. Each component exhibited the characteristic immunohistochemical properties, which were similar to those of the corresponding neuroendocrine neoplasms: Endocrine cells were positive for CAM 5.2, chromogranin A, and synaptophysin, like carcinoid tumor; ganglion-like cells were positive only for neurofilament, like ganglioneuroma; and spindle-shaped cells were positive for neurofilament and S-100 protein, like paraganglioma. These results agreed with those in gangliocytic paraganglioma of the duodenum. Pulmonary gangliocytic paraganglioma is similar to that in the duodenum, and is a hamartomatous proliferation of epithelial endocrine and neuronal cells of the bronchus.

Two interactive genes responsible for a new inherited cataract (RCT) in the mouse.

We discovered a mutant mouse, RCT (Rinshoken cataract), with a new congenital cataract in strain SJL/J. The opacity of the lens associated with microphthalmia could be observed visually at 3 to 3.5 months of age. Marked degeneration of the lens, including loss of the fine structure of the lens fibers and swelling of epithelial cells with vacuoles of various sizes in the cortex, but no other defects except photoreceptor degeneration in the retina, was detected. Histological change in the lens was first observed at 2 days after birth. No sex-related differences were detected, and normal phenotypes in the F1 progeny of RCT and normal mice indicated that the cataract was recessive. The chromosomal location of the causative gene was determined by interval mapping by using intersubspecific backcross progeny of RCT and MSM/Ms, an inbred strain from the Japanese wild mouse Mus musculus molossinus. Backcross progeny were divided into three groups according to phenotype: mice (1) with an early-onset cataract, which can be detected visually as in RCT mice, (2) with a late-onset cataract, which can be detected histologically but not visually, and (3) with a normal lens. Three phenotypes were found to be expressed by allele combinations of two recessive genes, rct and mrct (a modifier of rct). The rct locus essential for the onset of the cataract was tightly linked to D4Mit278 on Chromosome (Chr) 4 with no recombination. The mrct locus was closely linked to D5Mit239 (chi2 = 66.3, P << 0.00001) on Chr 5.

Recruitment of nonexpanded polyglutamine proteins to intranuclear aggregates in neuronal intranuclear hyaline inclusion disease.

Recruitment of polyglutamine-containing proteins into nuclear inclusions (NIs) was investigated in neuronal intranuclear hyaline inclusion disease (NIHID). Some polyglutamine-containing proteins, ataxin-2, ataxin-3, and TATA box binding protein (TBP), as well as unidentified proteins with expanded polyglutamine tracts were recruited into NIs with different frequencies. Ataxin-3 was incorporated into most of the NIs and disappeared from its normal cytoplasmic localization, whereas only a small fraction of NIs contained ataxin-2 and TBP. The consistent presence of ataxin-3 in NIs could reflect a biological feature of wild-type ataxin-3, which is translocated into the nucleus under pathological conditions and participates in the formation of aggregates. Ataxin-2 also accumulated in the nucleus, but was not necessarily incorporated into NIs, suggesting that transport of these cytoplasmic proteins into the nucleus and their recruitment into NIs are not wholly explained by an interaction with a polyglutamine stretch and must be regulated in part by other mechanisms. The prevalence of ubiquitin-immunopositive NIs was inversely correlated to neuronal loss in all cases examined. This correlation could be explained if NI formation is a protective mechanism involving the ubiquitin-proteasome pathway. This hypothesis is supported by the finding that the polyglutamine epitope in the center of NIs was surrounded by ubiquitin.

Inhibition of cytochrome c release in Fas-mediated signaling pathway in transgenic mice induced to express hepatitis C viral proteins.

Persistent hepatitis C virus (HCV) infection often progresses to chronic hepatitis, cirrhosis, and hepatocellular carcinoma. Numerous viruses have been reported to escape from apoptotic mechanism to maintain persistent infection. In the present study, we characterized the effect of HCV proteins on the Fas signal using HCV transgenic mice, which expressed core, E1, E2, and NS2 proteins, regulated by the Cre/loxP switching system. The transgene expression of HCV transgenic mice caused resistance to Fas antibody stimulated lethality. Apoptotic cell death in the liver of HCV protein expressing mice was significantly reduced compared with nonexpressing mice. Histopathological analysis and DNA fragmentation analysis revealed that the HCV proteins suppressed Fas-mediated apoptotic cell death. To identify the target pathway of HCV proteins, we characterized caspase activity. The activation of caspase-9 and -3/7 but not caspase-8 was inhibited by HCV proteins. Cytochrome c release from mitochondria was inhibited in HCV protein expressing mice. These results indicated that the expression of HCV proteins may directly or indirectly inhibit Fas-mediated apoptosis and death in mice by repressing the release of cytochrome c from mitochondria, thereby suppressing caspase-9 and -3/7 activation. These results suggest that HCV may cause persistent infection, as a result of suppression of Fas-mediated cell death.

Primary sclerosing cholangitis complicated with idiopathic thrombocytopenic purpura.

We present a 66-year-old woman with primary sclerosing cholangitis (PSC) complicated with idiopathic thrombocytopenic purpura (ITP). Both PSC and ITP are considered to reflect an immunological disturbance. However, their coexistence is very rare and to the best of our knowledge this is only the second reported case. In Japan, PSC patients are rarely treated with liver transplantation. Fortunately, the present patient underwent successful hepatic transplantation from a brain-dead donor and simultaneous splenectomy. This case emphasizes the importance of liver transplantation as an effective treatment for primary sclerosing cholangitis.

Nuclear localization of immunoreactive beta-catenin is specific to familial adenomatous polyposis in papillary thyroid carcinoma.

Thyroid carcinoma is the first symptom in some patients with familial adenomatous polyposis (FAP). We evaluated the cellular localization of beta-catenin in thyroid carcinomas associated (n = 4) or not associated (n = 173) with FAP, since loss of functional protein of the adenomatous polyposis coli (APC) gene leads to nuclear accumulation of beta-catenin in adenomas and carcinomas of the FAP colon. Immunoreactive beta-catenin was demonstrated at the cell membrane of glandular cells of the non-neoplastic thyroid and non-FAP carcinomas. On the other hand, cytoplasmic and nuclear accumulation of beta-catenin is specific to FAP-associated papillary carcinomas. The abnormality in the APC / beta-catenin pathway is thus also important in FAP-associated thyroid carcinoma, and beta-catenin immunohistochemistry is a feasible screening method to identify occult FAP in young patients with thyroid tumors.

CD70 expression in thymic carcinoma.

CD70, a type II transmembrane glycoprotein, is a member of the tumor necrosis factor (TNF) family that mediates the interaction between B- and T-lymphocytes. CD70 has been shown to be expressed by malignant lymphoma, especially Hodgkin's disease, and by nasopharyngeal carcinoma, both of which are frequently associated with Epstein-Barr virus (EBV). In this study, we investigated the expression of CD70 in epithelial cells of various types of thymic epithelial tumors and its association with EBV. Immunohistochemical expression of CD70 was studied on frozen tissue. In a series of 27 thymic epithelial tumors, including thymic carcinomas (n = 8), atypical thymomas (n = 5), thymomas (n = 13), and thymic carcinoid (n = 1), 7 (88%) thymic carcinomas and 1 (20%) atypical thymoma showed positive immunoreactivity for CD70, whereas CD70 was not detected in other tumors. Twenty-four intrathoracic malignant epithelial tumors of nonthymic origin, including lung (n = 17), esophagus (n = 5), and mesothelium (n = 2), showed no immunoreactivity for CD70. Northern blot analysis also revealed that CD70 messenger RNA was expressed in 2 of 2 thymic carcinomas, 0 of 2 atypical thymomas. and 0 of 2 thymomas. All of the 27 thymic epithelial tumors were EBV-negative as assessed by EBV-encoded small RNA in situ hybridization. The expression of CD70 is closely related to the pathogenesis of thymic carcinoma but unrelated to EBV infection in the thymus.

Granulocytic sarcoma of the thymus in a nonleukaemic patient.

We report a case of granulocytic sarcoma arising from the thymus in a 17-year-old nonleukaemic patient. The patient presented with an anterior mediastinal tumour and underwent surgical resection. Histological examination showed a diffuse infiltrate of immature round cells in the thymus. Tumour cells were diffusely peroxidase positive, but naphthol AS-D chloroacetate esterase negative. Immunohistochemical staining revealed expression of CD34 and terminal deoxynucleotidyl transferase (TdT), but not of CD13 and CD33. Ultrastructurally, electron-dense or medium-density granules were present in the cytoplasm. Four months after successful autogenic bone marrow transplantation, pleural and pericardial fluid contained tumour cells with azurophilic granules, which expressed CD13 and CD33, but not CD34 and TdT. The patient died of the disease 18 months after clinical manifestation, but still without developing leukaemia. The granulocytic sarcoma in the present case may have originated from myeloid precursors in the thymus and remained within the extramedullary site despite the differentiation into a more committed myeloid lineage at the relapse.

Microsatellite instability and loss of heterozygosity in primary and secondary proliferative lesions of the parathyroid gland.

Clonality and genetic abnormalities were evaluated to characterize proliferative lesions of the parathyroid gland. Fourteen lesions from patients with single-gland proliferation (adenomas [PA]), 6 lesions from patients with multiple-gland proliferation (primary hyperparathyroidism [PHPT]), and 47 lesions from 16 patients with secondary hyperparathyroidism (SHPT) were examined. Based on the X chromatin inactivation pattern, which was revealed by a HUMARA assay of lesions from female patients (n = 34; 24 informative cases), monoclonality was demonstrated in 6 of 10 PA (60%), 2 of 5 PHPT (40%), and 6 of 9 SHPT lesions (14 of 27 lesions, 52%). By PCR analysis using 17 microsatellite markers on eight chromosomes (chromosomes 1, 2, 3, 5, 6, 11, 13, and 17), loss of heterozygosity was sporadically observed in 4 of 14 PA, 3 of 6 PHPT, and 7 of 47 SHPT lesions, in most cases on a single locus of chromosome 11. On the other hand, microsatellite instability was observed more frequently: ie, in six PA, five PHPT, and nine SHPT lesions. The profile of microsatellite instability depended on the type of proliferation: microsatellite instability (MI) seemed to cluster in the region of chromosome 11 in PA. Microsatellite instability on TP53 was observed in 3 of 6 PHPT lesions and in 2 of 47 SHPT lesions but in no PA lesions. Microsatellite instability on Mfd47 was observed in only some cases of SHPT. Although no significant correlation was identified among histologic features, clonality, and genetic abnormalities in cases of primary proliferation, genetic abnormalities were more frequently observed in SHPT lesions that lacked fat tissues. Thus, genetic instability might be important in proliferative disorders of the parathyroid gland, either with or without uremia. However, genetic instability seems to be induced by different mechanisms in the three types of proliferation studied. In SHPT, the absence of fat tissues may indicate that the proliferation is accompanied by genetic changes.