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Helmut Friess

Publications and source records attributed to Helmut Friess.

At least 55 records · Page 3Linked to original sources
PubMed2006

Pancreatic cancer: from bench to 5-year survival.

Pancreatic ductal adenocarcinoma is one of the most aggressive human malignancies, with an overall 5-year survival rate of less than 4%. On the molecular level, an increasing number of genetic and epigenetic alterations have been discovered, with a particular focus on growth factors and related pathways. Small-molecule tyrosine kinase inhibitors, antibodies, and other approaches have been developed in recent years to target these signal transduction pathways, and first clinical trials show encouraging results. In addition, molecular alterations have been identified that enable the cancer cells to invade the perineurium and the retroperitoneal space, thus explaining at least in part the high rate of local recurrence and the severe pain syndrome. Technically, pancreatic surgery has advanced, with acceptable morbidity and mortality rates in high-volume centers. Randomized controlled trials are increasingly carried out to define the best palliative and adjuvant therapy for this disease. Translational research combined with clinical trials will hopefully lead to improved survival and better quality of life for pancreatic cancer patients in the future.

Animals↗
PubMed2006

The neurotrophic factor artemin promotes pancreatic cancer invasion.

OBJECTIVE: To analyze the role of Artemin in pancreatic ductal adenocarcinoma (PDAC) in terms of expression, influence on cancer cell behavior, and pain correlation. SUMMARY BACKGROUND DATA: PDAC is characterized by prominent local nerve alterations and perineural invasion, which frequently affects the extrapancreatic nerve plexus, causing severe pain and precluding curative resection. Artemin, a neurotrophic protein controlling growth, regeneration, and survival of neurons was analyzed to highlight the neuro-cancer interactions in PDAC. METHODS: Artemin and its receptors (GFRalpha3/RET) were studied in PDAC tissues and normal pancreas by Western blot analysis and immunohistochemistry. RNA expression was analyzed in pancreatic tissues (normal, cancer) and pancreatic cancer cell lines by QRT-PCR. To evaluate whether Artemin influences cancer cell proliferation and invasion, MTT-growth and Matrigel-invasion assays were used. In addition, the tissue expression of Artemin was correlated with pain in PDAC. RESULTS: Artemin and GFRalpha3/RET were both detected at enhanced levels in PDAC compared with normal pancreas, localizing predominantly in hypertrophic nerves and arterial walls, as well as in cancer cells of primary and metastatic lesions. The levels of Artemin and GFRalpha3 did not correlate with pain in PDAC patients. However, Artemin promoted pancreatic cancer cell invasion up to 5-fold, without affecting cancer cell proliferation. CONCLUSION: Artemin expression was not associated with pain in PDAC. However by increasing cancer cell invasion, Artemin seems to influence neural invasion and thereby contribute to cancer cell spreading along pancreatic nerves.

Adenocarcinoma↗
PubMed2006

Middle segmental pancreatic resection: An option to treat benign pancreatic body lesions.

OBJECTIVE: To clarify whether middle segmental pancreatic resection can be performed with comparable morbidity and mortality to classic pancreatic resections for lesions in the mid-portion of the pancreas. SUMMARY BACKGROUND DATA: Pancreaticoduodenectomies or distal pancreatectomy, traditionally used to treat lesions of the pancreatic body, sacrifice a significant amount of normal pancreatic tissue. Middle segmental pancreatic resection has therefore been introduced to minimize loss of functioning pancreatic tissue. PATIENTS AND METHODS: In a prospective 4-year single-center study, 40 consecutive patients with lesions of the neck or the body of the pancreas underwent a middle segmental pancreatic resection. A matched-pairs analysis comparing middle segmental pancreatic resection with pp-Whipple and distal pancreatectomy was included. RESULTS: Seventeen patients had neoplastic lesions (4 solid malignancies, 9 cystic lesions, 4 neuroendocrine tumors) and 23 patients had focal chronic pancreatitis. Postoperative surgical morbidity was 27.5% and mortality 2.5%. The reoperation rate was 5.0%. Three patients (7.5%) developed pancreatic fistula. Median postoperative hospital stay was 11 days (range, 6-62 days). After a median follow-up of 29 months, 97.4% (38 patients) of the patients were satisfied with the operation. The mean quality of life status (EORTC QLQ-C30) was comparable to a normal control population. Matched-pairs analysis revealed no differences of perioperative parameters (except operation time), morbidity, and mortality. However, endocrine pancreatic function was better preserved (P < 0.05) in patients with middle segmental pancreatic resection. CONCLUSIONS: Middle segmental pancreatic resection is an appropriate procedure for selected patients with tumorous lesions in the mid-portion of the pancreas. It preserves pancreatic parenchyma and function and has a mortality and morbidity rate comparable to other pancreatic resection procedures.

Adolescent↗
PubMed2006

Update on pancreatic cancer and alcohol-associated risk.

Ductal adenocarcinoma of the pancreas is characterized by extremely aggressive behavior, with an overall 5-year survival of <4%. Because conventional and specifically tailored therapeutic regimens have little impact on patient survival, epidemiological and molecular research aims at identifying and reducing risk factors. Cigarette smoking, obesity, diabetes mellitus, and chronic pancreatitis are amenable to medical prevention or therapy. Heavy alcohol consumption is an inconsistent single risk factor for pancreatic cancer but may promote carcinogenesis by increasing the risk of diabetes mellitus or chronic pancreatitis. For various agents, the key carcinogenic effect is probably an inflammatory response in the pancreatic tissue. On the molecular level, mutations of oncogenes and tumor suppressor genes, as well as various epigenetic alterations, such as overexpression of growth factors and their receptors, are important in tumorigenesis. Complete and safe surgical resection, together with adjuvant therapy, offers prolonged survival, with 5-year survival rates of approximately 25%. However, for unresectable or disseminated disease, which constitutes the vast majority of cases, treatment is palliative. Despite increasing knowledge about the molecular pathology of pancreatic cancer and despite advances in treatment, the overall course of the disease is dismal, and reinforced efforts to reduce incidence and improve outcome are needed desperately.

Adenocarcinoma↗
PubMed2006

Role of lymphangiogenesis and lymphangiogenic factors during pancreatic cancer progression and lymphatic spread.

Treatment options for ductal adenocarcinoma of the pancreas are limited by early lymphatic spread, but the lymphatic vessels in pancreatic carcinoma have not been studied to date. Here, we present a histomorphological analysis of lymphatic vessels in pancreatic cancer resection specimens. Both intratumoral and peritumoral tissue were devoid of active lymphangiogenesis. Intratumoral lymphatics were frequently collapsed and non-functional, whereas peritumoral lymphatic vessels were enlarged, and numerous lymphatic vessels were seen in metastases. In addition, we screened pancreatic cancer tissue and pancreatic carcinoma cell lines for mRNA expression of the lymphangiogenic growth factor, VEGF-C; its receptor, VEGFR-3/flt4; and Prox1, a transcription factor essential for embryonic development of both lymphatic vessels and the pancreatic bud. VEGF-C was abundantly expressed in pancreatic cancer tissue and -cell lines and VEGFR-3/flt4 was expressed in cancer stromal cells. Prox1 was strongly expressed in the normal exocrine pancreas but significantly reduced in pancreatic cancer specimens from patients with short survival rates. Well-differentiated cell lines displayed higher levels of Prox1 mRNA than poorly differentiated ones. These results suggest that active lymphangiogenesis is not required for lymphovascular spread of pancreatic cancer. VEGF-C may promote local tumor growth via paracrine signaling to stromal cells expressing VEGFR-3 and support the entry of cancer cells into peritumoral lymphatics. Furthermore, loss of Prox1 function may be a driving force behind pancreatic carcinoma progression.

Angiogenesis Inducing Agents↗
PubMed2006

A new tool for experimental tumour research.

Surgical resected tumours are often stored for hours in the clinic upon transfer to the bench leading to apoptosis of tumour cells making them no longer suitable for molecular analysis and diagnostic procedures. The way out of this problem may be a new oxygen-enriched solution (OES). We tested this agent using surgical resections of carcinomas of lung, rectum and pancreas. Immediately after resection, one part of each individual tumour was stored in PBS and the other part in OES, and the content of viable or dead cells was determined by trypan blue exclusion and MTT-assay. We found that OES keeps tumour cells up to 3 days and longer more viable than PBS and reduces the percentage of dead cells without inducing therapy resistance and affecting the outcome of experimental procedures. Thus, storing freshly resected tumours in OES may save time for tumour transfer and initiation of experiments.

Antineoplastic Agents↗
PubMed2006

Yes-associated protein (YAP65) in relation to Smad7 expression in human pancreatic ductal adenocarcinoma.

Pancreatic ductal adenocarcinoma (PDAC) is characterized by multiple alterations in the TGF-beta signaling pathway. Yes-associated protein (YAP65) interacts with Smad7 thereby influencing TGF-beta signaling. In the present study, the expression of YAP65 in PDAC was analyzed in order to elucidate the potential role of this molecule in the pathogenesis of pancreatic cancer. YAP65 mRNA expression levels in human pancreatic tissue samples and cell lines were analyzed by Northern blotting and quantitative RT-PCR. Immunohistochemistry was carried out to localize and quantify YAP65 expression in relation to Smad7 expression and Smad4 mutations. The effects of TGF-beta1 on Smad7 and YAP65 mRNA expression were analyzed by quantitative RT-PCR. Enhanced expression of YAP65 mRNA was identified by Northern blotting and quantitative RT-PCR in PDAC in comparison to the normal pancreas (2.5-fold increase) and to chronic pancreatitis (1.3-fold increase). In the normal pancreas, YAP65 was absent in acinar cells, large ducts and islet cells, but exhibited moderate to strong immunoreactivity in centroacinar cells and ductules. Tubular complexes in CP and CP-like lesions in PDAC also exhibited strong staining. In contrast, weak to moderate YAP65 immunoreactivity was present in the cancer cells. There was no correlation between YAP65 immunostaining and Smad7 staining or Smad4 mutations in the cancer samples. TGF-beta1 strongly induced Smad7 mRNA in Colo-357 and in Panc-1 cells, but only slightly induced YAP65 mRNA in Colo-357 cells. In conclusion, YAP65 is expressed mainly in centroacinar and small ductal cells in the normal pancreas. In PDAC, YAP65 is present in tubular complexes and to a lesser extent in cancer cells. Together with the known function of YAP65 in different growth and differentiation regulating pathways, it is suggested that this gene plays a role in the normal and diseased pancreas.

Adaptor Proteins, Signal Transducing↗
PubMed2006

Correlation of glypican-1 expression with TGF-beta, BMP, and activin receptors in pancreatic ductal adenocarcinoma.

Glypican1 (GPC1) is a cell surface heparan sulfate proteoglycan that acts as a co-receptor for heparin-binding growth factors as well as for members of the TGF-beta family. GPC1 plays a role in pancreatic cancer by regulating growth factor responsiveness. In view of the importance of members of the TGF-beta family in pancreatic cancer, in the present study, the role of GPC1 in TGF-beta, BMP and activin signaling was analyzed. Quantitative RT-PCR and immunohistochemistry were utilized to analyze GPC1 and TGF-beta, BMP and activin receptor expression levels. Panc-1 and T3M4 pancreatic cancer cells were transfected in a stable manner with a GPC1 antisense expression construct. Anchorage-dependent and -independent growth was determined by MTT and soft agar assays. TGF-beta1, activin-A and BMP-2 responsiveness was determined by MTT assays and immunoblotting with p21, p-Smad1, and p-Smad2 antibodies. QRT-PCR demonstrated increased GPC1 mRNA levels in pancreatic ductal adenocarcinoma (PDAC) compared to normal pancreatic tissues (NPT), as described previously. There was a significant correlation between GPC1 mRNA levels and TbetaRII, act-R1a, act-R1b, act-R2a, BMP-R1a, and BMP-R2 mRNA expression in NPT. In contrast, GPC1 mRNA expression correlated directly with act-R1a and BMP-R1a in N0 PDAC cases and with act-R2a and BMP-R1a in lymph node positive cases. Down-regulation of GPC1 resulted in increased doubling time in Panc-1 but not in T3M4 cells, and decreased anchorage-independent growth in both cell lines. GPC1 down-regulation resulted in a slightly altered response towards TGF-beta1, activin-A and BMP-2 in terms of growth, p21 induction and Smad2 phosphorylation. In conclusion, enhanced GPC1 expression correlates with BMP and activin receptors in pancreatic cancer. GPC1 down-regulation suppresses pancreatic cancer cell growth and slightly modifies signaling of members of the TGF-beta family of growth factors.

Activin Receptors↗
PubMed2006

Corticosteroids induce chemotherapy resistance in the majority of tumour cells from bone, brain, breast, cervix, melanoma and neuroblastoma.

Glucocorticoids (GCs) such as dexamethasone (DEX) have been widely used as co-medication in cancer therapy because they have potent proapoptotic properties in lymphoid cells, can reduce nausea, and alleviate acute toxic effects in healthy tissue. However, GCs are used in a supportive-care role, even though no prospective clinical studies have assessed the effect of these steroids on the growth of solid tumours. Data from preclinical and, to some extent, clinical studies, suggest that GCs induce treatment resistance in some solid tumours. Since it is unknown whether GC-induced resistance occurs only occasionally or is a more common phenomenon, we performed a screening study using several established cell lines from bone, brain, breast and cervix carcinoma as well as melanoma and neuroblastoma together with fresh surgical resections from patients with breast cancer. We found that DEX inhibits cisplatin and 5-fluorouracil-induced apoptosis and promotes the growth of the majority of examined malignant cells. In contrast, and as expected, DEX acted pro-apoptotically and promoted the cytotoxic effect of chemotherapy in established and primary lymphoid cells. Thus, these data demonstrate the need for detailed molecular studies to clarify the mechanism of differential glucocorticoid signaling as well as controlled, prospective clinical studies.

Antineoplastic Agents, Hormonal↗
PubMed2005

Malignant vascular tumors: clinical presentation, surgical therapy, and long-term prognosis.

BACKGROUND: The aim of this study was to analyze the presentation of, surgery for, and prognosis of malignant vascular tumors (MVTs). METHODS: This was an observational single-center study. Patients who underwent operation for MVTs between 1988 and 2004 were included. Data were gathered prospectively in a computerized registry. RESULTS: Of 568 adult patients with soft tissue malignancies, 43 (7.6%) were treated for MVTs. Twenty-four men and 19 women (median age, 55.3 years) were referred for 30 primary tumors and 13 recurrences. Symptoms were observed in 90.7% of the cases (swelling [37.2%], pain [34.9%], extrusion [11.6%], hemorrhage [7%], weight loss [4.7%], loss of energy [4.7%], impaired function [4.7%], and others [30.2%]). Tumors were located in the extremities (n = 16), trunk (n = 3), abdomen (n = 15), retroperitoneum (n = 7), and thyroid gland (n = 2). Twenty-two (51.2%) angiosarcomas, nine (20.9%) malignant hemangiopericytomas, eight (18.6%) malignant epithelioid hemangioendotheliomas, and four (9.3%) lymphangiosarcomas were seen. The median overall survival after surgery was 21.4 months, with 2-, 5-, and 10-year overall survival rates of 41.5%, 38.3%, and 18.8%, respectively. MVTs of the extremities and trunk and localized disease indicated a better prognosis than abdominal or retroperitoneal MVTs (univariate and multivariate analyses: P = .0122 and P = .0287) and metastasized stages (univariate and multivariate analyses: P = .0187 and P = .0287). CONCLUSIONS: A considerable number of patients with soft tissue malignancies undergo surgery for MVT. Various symptoms and a multilocular occurrence are typical. The course of MVTs is aggressive. Tumor site and stage are important prognostic factors. Surgery is potentially curative, especially for localized disease of the extremities and trunk.

Adult↗
PubMed2005

Surgical treatment of primary hepatic epithelioid hemangioendothelioma.

Epithelioid hemangioendothelioma is a very rare tumor of vascular origin. It can develop in different tissues such as soft tissue, lung, or liver. Hepatic epithelioid hemangioendothelioma (HEH) mostly affects females. The malignant potential of HEH often remains unclear in the individual patient. It can range from benign hemangioma to malignant hemangioendotheliosarcoma. Here we present our experience with five patients with primary HEH, who were treated with curative intention in our department. All patients in our series with confirmed histological HEH did not show extrahepatic extension and consequently underwent surgical treatment. In three patients, liver transplantation (LTx) was performed (two cadaveric and one living related). In one patient, a right-sided hemihepatectomy with partial resection of the diaphragm was performed. One patient died while she was on the waiting list for LTx due to rapid tumor progression. Postoperative follow-up ranged from 1 to 13 years. No adjuvant chemotherapy was applied. Until now, no recurrence of local tumor or distant metastases could be observed during follow-up in our series. Early detection and surgical intervention in case of HEH can potentially offer curative treatment. The treatment of first choice appears to be radical liver resection. In our view, LTx represents a potentially important option for patients with a nonresectable tumor. Despite the long waiting time, its often unclear dignity, and a proven progressive growth pattern, living related LTx also plays a potentially important role. The 5-year overall survival rate of patients with HEH in the literature varies from 43% to 55%. Long-term survival of patients with HEH is significantly higher compared to other hepatic malignancies. The role of adjuvant therapy currently remains unclear.

Adult↗
PubMed2005

Evolution of liver transplantation at the University of Heidelberg: interventions influencing patient referral.

In Heidelberg, liver transplantation was first performed in 1987. In this article, we report our experience with an interdisciplinary approach (intervention) to improve the internal and external acceptance of the liver transplantation program. Formation of a transplant team and interdisciplinary standard setting of pre-, peri-, and postoperative protocols significantly stimulated this process. Involvement of the referring doctors in patient's treatment by transferring competencies enhanced patients referral to our center and increased the numbers of patients on the waiting list, an indispensable factor for organ allocation by Eurotransplant and transplantation. Involvement of patient organizations increased patient acceptance in the program.

Germany↗
PubMed2005

Indications for liver transplantation in patients with amyloidosis: a single-center experience with 11 cases.

Familial amyloidotic polyneuropathy (FAP) is an inherited disorder with the systemic deposition of amyloid fibrils containing mutant transthyretin variants. The mutant form of transthyretin amyloidosis is produced mainly in the liver. Successful liver transplantation (LTx) could eliminate the source of the variant transthyretin molecule, and is now the only known curative treatment. The aim of this study is to evaluate the results of LTx for FAP at the University of Heidelberg. Eleven patients who underwent LTx between 1985 and 2004 with the diagnosis of FAP were evaluated. Of 11 patients, seven (64%) were male and four (36%) were female. The mean age was 49.5 years (range 27-70). Met 30 (n=5) was the most common type of amyloidosis followed by Arg 50 (n=3), Val 107 (n=2), and Phe 33 (n=1). All of the patients were selected for LTx and Domino LTx was performed in six patients. The majority (80%) of the patients with type Met 30 amyloidosis are alive, whereas in other types of amyloidosis only 33% are living. This finding emphasizes better prognosis of Met 30 variant of FAP in comparison to other variants such as Arg 50, Val 107, and Phe 33. After LTx, improvement of clinical symptoms (completely or partially) was observed in six patients (55%). In conclusion, LTx is considered as the only therapeutic alternative in patients with amyloidosis accompanied by hepatic synthesis of the amyloid protein. The most important risk factors for LTx can be predicted by assessing the nutritional condition of the patient, the duration of the disease, and the amyloid variant. Therefore, precise diagnostic measures are required before listing a patient for LTx. Domino LTx is an acceptable form of LTx that can preserve the pool of organ donors. In order to stop the progression of FAP, LTx would be justified in a subgroup of patients with amyloidosis. Based on our results, we support the idea that the effectiveness of extended preoperative period before LTx or the transplantation of other transthyretin variants other than Met 30 is questionable.

Adult↗
PubMed2005

Living related liver transplantation: the ultimate technique to expand the donor pool?

Today, living donor liver transplantation (LDLT) is well established in many centers as a therapeutic method for end-stage liver disease. LDLT is an option for selected cases and is still under development. From the beginning of LDLT until now, many innovations have been presented and as a consequence both the surgical and medical complications in both donors and recipients reduced greatly. As a benefit, this procedure enriches the donor organ pool and reduces the imbalance between the scarcity of organ resource and organ demand; however, LDLT will not solve the problem of organ shortage. Because the modality of LDLT is still associated with morbidity and mortality of the donors, recipient's graft-size match problems and substantial surgical complications, ethical issues of live organ donation must be discussed. Nevertheless, estimates of patient survival and complications in both donors and recipients should incorporate waiting time mortality. With this background, the extended indications for LDLT compared with cadaveric liver transplantation would have to be discussed in many cases. In this brief review, we focus on potential complications for both donors and recipients after adult-to-adult LDLT, discuss ethical problems and controversies with special interest on the perspective and potentials of this surgical method.

Cadaver↗
PubMed2005

Acute retinopathy following pancreatic head resection for chronic pancreatitis: a rare, severe complication.

CONTEXT: Chronic pancreatitis is a pancreatic disorder affecting endocrine and exocrine pancreatic functions with a variety of mainly abdominal symptoms. CASE REPORT: We report the rare complication of acute retinopathy with visual loss following pancreatic head resection due to chronic pancreatitis. CONCLUSIONS: Acute retinal dysfunction is a rare severe complication of acute and chronic pancreatitis. Early recognition and therapy are of utmost importance in restoring normal visual acuity and avoiding irreversible damage.

Acute Disease↗
PubMed2005

Pancreatic metastasis of Merkel cell carcinoma and concomitant insulinoma: case report and literature review.

BACKGROUND: Merkel cell carcinomas are rare neoplasm of neuroendocrine origin, usually observed in elderly people in areas with abundant sunlight, and predominantly located on the head and neck, extremities, and trunk. In many patients, a local recurrence after resection of the primary tumour and even distant metastases can be found. CASE PRESENTATION: We report an unusual occurrence of pancreatic metastases from a previously diagnosed Merkel cell carcinoma with the discovery of a concomitant insulinoma. An 82-year old lady suffered from recurrent attacks of hypoglycemia and presented with an abdominal mass, 2 years prior she had an excision done on her eyebrow that was reported as Merkel cell carcinoma. An extended distal pancreatectomy and splenectomy along with resection of the left flexure of the colon for her abdominal mass was carried out. Final histopathology of the mass was a poorly differentiated endocrine carcinoma in the pancreatic tail, in the peripancreatic tissue and in the surrounding soft tissue consistent with metastatic Merkel cell carcinoma in addition to an insulinoma of the pancreatic body. CONCLUSION: This is the first documented case of a metastatic Merkel cell carcinoma and a concomitant insulinoma, suggesting either a mere coincidence or an unknown neuroendocrine tumor syndrome.

Journal Article↗
PubMed2005

Delayed gastric emptying and intestinal hormones following pancreatoduodenectomy.

BACKGROUND/AIMS: Delayed gastric emptying (DGE) is frequently reported in patients following pancreatoduodenectomy (PD). The present study tested the hypothesis that gastrointestinal hormones known to effect gastric emptying contribute to DGE in patients after PD. METHODS: Patients with (delayed, n = 9) or without clinical signs of DGE (non-delayed, n = 22) after PD were investigated. Plasma concentrations of motilin, glucagon-like peptide-1 (GLP-1), neurotensin, and peptide YY (PYY) and the gastric emptying rate (GER), assessed by the paracetamol absorption method were measured after a liquid meal on postoperative day 11. RESULTS: Days with a nasogastric tube (p < 0.01), days until solid food was tolerated (p < 0.05), and hospital stay (p < 0.001) were increased in delayed compared to non-delayed patients. The total and incremental integrated peptide responses of motilin and GLP-1 were similar, but the responses of neurotensin and PYY were reduced, in delayed compared to non-delayed patients, whether considered on clinical grounds or by measured GER (p < 0.05-0.005). CONCLUSION: Neurotensin and PYY slow the rate of gastric emptying in humans. Therefore, our findings suggest that reduced hormone responses were the consequence of DGE arising from delayed delivery of nutrients to the distal intestine where the endocrine cells secrete neurotensin and PYY reside.

Acetaminophen↗