Gastrointestinal stromal tumors treatment in the Imatinib era. The role of fair indication

AIM

Gastrointestinal stromal tumor (GIST) is the most common mesenchymal tumor of the gastrointestinal tract. Surgery remains the elective treatment. We retrospectively compared two group of patients, who underwent surgery for GIST before and after Imatinib advent in order to analyze the recurrence and survival rate.

METHODS

Two patient groups who underwent surgery for GIST, from January 1997 to December 2002 (Pre-Imatinib group) and from January 2003 to December 2008 (Post-Imatinib group) were compared. Patients were evaluated on the base of gender, age, clinical manifestations, primary location and metastasis positivity, tumor size, mitotic index, immunoreactivity for CD117 and the outcome, including date of death.

RESULTS

In the Pre-IM group only one patient died for prostate cancer, 12 months after operation, the other died because of GIST with a 24.6 months of median survival rate (range 15-51). In the remaining 12 patients the median follow up period was 55 months (range 6-152 months). In the Post-IM group the mean follow up was 50.7 months (range 26-74) and they are still being assessed for oncological as well as surgical treatment.

CONCLUSION

Early diagnosis and radical resection remain the standard of cure for GISTs. To date, the use of Imatinib lead to its utilization as adjuvant and neo-adjuvant therapy in adults. Our experience suggests that there is a correlation between the mutational status of KIT and clinical outcome. These aspects should be explored for targeted therapy that can effectively combine biological therapy to surgery.

Explant-derived human dental pulp stem cells enhance differentiation and proliferation potentials

Numerous stem cell niches are present in the different tissues and organs of the adult human body. Among these tissues, dental pulp, entrapped within the ‘sealed niche’ of the pulp chamber, is an extremely rich site for collecting stem cells. In this study, we demonstrate that the isolation of human dental pulp stem cells by the explants culture method (hD-DPSCs) allows the recovery of a population of dental mesenchymal stem cells that exhibit an elevated proliferation potential. Moreover, we highlight that hD-DPSCs are not only capable of differentiating into osteoblasts and chondrocytes but are also able to switch their genetic programme when co-cultured with murine myoblasts. High levels of MyoD expression were detected, indicating that muscle-specific genes in dental pulp cells can be turned on through myogenic fusion, confirming thus their multipotency. A perivascular niche may be the potential source of hD-DPSCs, as suggested by the consistent Ca²⁺ release from these cells in response to endothelin-1 (ET-1) treatment, which is also able to significantly increase cell proliferation. Moreover, response to ET-1 has been found to be superior in hD-DPSCs than in DPSCs, probably due to the isolation method that promotes release of stem/progenitor cells from perivascular structures. The ability to isolate, expand and direct the differentiation of hD-DPSCs into several lineages, mainly towards myogenesis, offers an opportunity for the study of events associated with cell commitment and differentiation. Therefore, hD-DPSCs display enhanced differentiation abilities when compared to DPSCs, and this might be of relevance for their use in therapy.

[Incisional hernia prosthetic surgery: a prospective study comparing laparoscopic and open techniques]

BACKGROUND

Incisional hernia is a common complication of abdominal surgery and it is often a source of long-term morbidity. Surgical treatment include many different techniques and up to today the choice may be difficult. The employment of prosthetic materials has contributed to a remarkable improvement in the results of this surgery. We performed a prospective study to compare the outcomes after laparoscopic and open incisional hernia repair.

PATIENTS AND METHODS

A total of 60 patients were assigned at random to two groups to be operated for median incisional hernia with mesh. Of these, 30 underwent laparoscopic repair and 30 open repair performed by Rives-Stoppa technique. Early and long-term outcomes were analyzed by a median follow-up of 45 months (range 31-78). Statistical analysis was done to asses differences between the groups.

RESULTS

Both groups were homogeneus in terms of patient age, sex, body mass index, American Society of Anesthesiologists score and incisional hernia features. Laparoscopic repair is associated with a significantly lower incidence of wound infections, shorter operative time and hospitalization and faster return to work. The recurrence rate was similar between the two groups.

CONCLUSION

In our experience laparoscopic incisional hernia repair appear to be a safe, feasible and effective alternative to Rives-Stoppa technique.

[Open mesh technique versus laparoscopic transabdominal preperitoneal (TAPP) approach in inguinal hernia repair. Our experience]

BACKGROUND

In the last ten years the introduction of various open mesh and laparoscopic techniques has increased the interest in inguinal hernia surgery. Anyway controversy persists about the most effective inguinal hernia repair. The aim of this study was to compare the results of open mesh technique and laparoscopic transabdominal preperitoneal (TAPP) repair for inguinal hernia.

PATIENTS AND METHODS

We considered 584 patients, 532 man and 52 woman, between 19 and 86 years: 332 (56.8%) had open mesh repair and 252 (43.2%) laparoscopic TAPP repair of groin hernia. Operative time, complications, recurrences and time to normal activities were recorded in both groups (range follow-up 1-10 years).

RESULTS

The median operative time was 71 min for open group and 92 min for TAPP group. No intraoperative complications were observed. Postoperative complication rate was 4,5% in patients open group and 3% in TAPP group. The recurrence rate was less than 1% in both groups (0,6% for open repair and 0,4% for laparoscopic repair). Significant difference was observed in the median time to return to normal activities: 9,8 days in TAPP group versus 13,4 days in open approach.

CONCLUSIONS

Our experience confirmed the safety and effectiveness of laparoscopic transabdominal preperitoneal (TAPP) approach to inguinal hernia repair as excellent alternative to conventional surgery. The reduction of operative time, complications and recurrences is correlated to the surgeon's experience and learning curve.

[Reoperative thyroid surgery: personal experience and review of the literature]

The goal of this study was to evaluate the complication rate of reoperative thyroid surgery and to find out the way to minimize the morbidity associated with it. We reviewed our experience in 622 patients, who underwent thyroid operation from January 2000 to September 2007. Among these ones, 76 were the patients who underwent reoperative thyroid surgery. Prior surgery in the 76 reoperations was: nucleo-resection in 9 pts (12.9%), lobectomy in 43 pts (55.5%), lobectomy+isthmectomy in 7 pts (9.3%), subtotal thyroidectomy in 17 pts (22.2%). Histologic examination revealed: benign lesions in 67 pts (88.15%), papillary cancer in 4 pts (5.26%), follicular cancer in 2 pts (2.63%), follicular adenoma in 1 pt (1.32%) and Hashimoto thyroiditis in 2 pts (2.63%). Complications included: section of recurrent laryngeal nerve, that was reconstructed in the same operation, and bilateral palsy of the recurrent laryngeal nerve so that was necessary to make a tracheotomy. One of the patient at the first thyroid surgery had monolateral palsy of the recurrent laryngeal nerve with dyspnoea and dysphonia. Temporary hypoparathyroidism (Ca<8 mg/dl) occurred in 47.3% of the patients, who underwent reoperative thyroid surgery and in 45.2% of the patients, who underwent prior thyroid surgery. Conclusions. This study documents that reoperative thyroid surgery can be performed with little morbidity to the patient if precise operative rules are respected.

[Low-protein diet and nutritional status]

Low-protein diets (LPDs) are most useful to control uremic symptoms, but the fear of malnutrition is still an issue. Thanks to commercially available low-protein preparations, reducing the protein intake to 0.6 mg/kg/day and even 0.3 mg/kg/day (very low-protein diets, VLPDs) is quite easy. However, providing palatable low-protein diets without disrupting the patient's lifestyle may not be as easy as reducing the protein intake. The risk is a low compliance with the dietary prescription, resulting in reduction of calorie intake and malnutrition. The risk is even higher in patients beginning dialysis, for some degree of malnutrition is frequent in such subjects. Preserving an adequate nutritional situation is feasible for a long time in LPD-treated and VLPD-treated kidney patients independently of age and diabetes, as demonstrated by the MDRD study. Careful follow-up of protein and calorie intake as well as nutritional status is, however, required. Several anthropometric, laboratory, clinical, and bioelectrical impedance indices are available for follow-up. Moderate yet steady physical activity is highly advisable in patients with progressive renal disease.

[Low-protein diet in Italy today: the conclusions of the Working Group from the Italian Society of Nephrology]

The high estimated prevalence of chronic kidney disease (CKD) forcefully supports the need for collaboration among nephrologists, cardiologists, diabetologists and general practitioners, to reduce the cardiovascular risk of CKD patients and delay the start of dialysis. Many studies confirm that reducing the dietary intake of proteins improves uremia as well as acid-base and phosphorus disorders without exposing the CKD patient to the risk of malnutrition. The possibility of delaying renal death and the start of dialysis by almost one to two years is also recognized, thanks in part to the antiproteinuric effect of low-protein diets supplemented with keto acids and essential amino acids. Reducing the dietary protein intake delays the start of dialysis independently of the effect of renin-angiotensin system (RAS)-active antihypertensive drugs. Reduction of the dietary protein intake is indicated in patients with a glomerular filtration rate <25 mL/min (CKD stages 4 and 5). Some situations may, however, require an earlier switch to a low-protein diet, e.g., high proteinuria, renal function worsening at more than 5 mL/min/year, diabetes, and metabolic decompensation. If well designed and properly carried out, reduction of the dietary intake of proteins is not associated with low serum albumin levels or malnutrition, and does not affect patients death. Today, highly palatable, high-quality reduced protein preparations are widely available to reduce the protein intake of CKD patients.

[Low-protein dietary therapy in patients with chronic kidney disease]

Several prospective studies and meta-analyses including the recent Cochrane meta-analysis have demonstrated that reducing the protein content in the diet delays renal death and the start of dialysis in patients with chronic kidney disease (CKD). Reducing the dietary protein intake offers other benefits such as lowering accumulation of uremic toxins and circulating phosphates and improving symptoms and metabolic derangements. Following the publication of the Cochrane meta-analysis, some of the most renowned experts in Italy on dietary therapy in the CKD patient established a working group within the Italian Society of Nephrology (SIN), the ''Nephrontieres'' project. The current supplement of GIN presents the views of the members of the ''Nephrontieres'' group on a range of issues related to dietary therapy in CKD. A CME program for Italian nephrologists also originated from the collaborative work of the group.

[Extraperitoneal rectal cancer surgery]

Despite recent advances in radiation and chemotherapy, surgical resection remains the only potentially curative procedure for rectal cancer. The introduction of total mesorectal excision with autonomic pelvic nerve sparing and new modalities in restoring bowel continuity has improved significantly the prognosis as well as life quality of rectal cancer patients. Better results will be achieved only with a correct multidisciplinary approach. The Authors report their experience with surgical treatment of extraperitoneal rectal cancer, examine some important technical innovation and emphasize the oncological principles of radical surgery.

Efficacy and safety of once-weekly intravenous epoetin alfa in maintaining hemoglobin levels in hemodialysis patients

BACKGROUND

Although an erythropoiesis-stimulating agent (ESA) is most frequently administered intravenously for treatment of anemia in patients with chronic kidney disease who are on dialysis, few studies have compared the efficacy of different intravenous (i.v.) dosing schedules.

METHODS

This multicenter, phase IIIb, open-label, controlled study randomized 289 stable hemodialysis patients to continue with conventional dosing of i.v. epoetin alfa or darbepoetin, or to switch to once-weekly i.v. epoetin alfa at the same cumulative weekly starting dose, to maintain hemoglobin levels at 11.0-13.0 g/dL, and within 1.0 g/dL of the baseline value. Hemoglobin levels and ESA doses were recorded every 4 weeks for 28 weeks.

RESULTS

Hemoglobin levels fell significantly and ESA doses increased significantly between baseline and week 28 (mean of week 16-28 values) in the once-weekly epoetin alfa group, compared with the conventional treatment group (p< 0.001). The adjusted difference in mean hemoglobin levels between the groups was 0.73 g/dL (greater than the threshold for therapeutic equivalence of 0.5 g/dL). The changes between groups from baseline was significant at all time points for hemoglobin levels (0.36, 0.46, 0.81, 0.87, 0.78, 0.62 and 0.49 g/dL) and from week 12 for ESA dose (718.5, 1,326.5, 1,732.0, 1,839.7 and 1,959.1 IU/week; p=0.005). Hemoglobin was maintained at the target level in 78% and 84% of patients on conventional dosing, and 67% and 64% of those on once-weekly epoetin alfa in the intention-to-treat (p=0.1) and per protocol (p=0.016) populations, respectively.

CONCLUSIONS

This study did not show therapeutic equivalence of once-weekly i.v. epoetin alfa with conventional dosing regimens.

Clinical non-instrumental evaluation of dysphagia

Clinical non-instrumental evaluation plays an important role in the assessment of the dysphagic patient. This evaluation, called "bedside examination", aims to establish whether dysphagia is present, evaluating severity, determining the alterations which cause it, planning rehabilitation, testing outcome of treatment. The assessment takes into consideration anamnesis regarding the swallowing problem, evaluation of the anatomy and functionality, of sensitivity and the reflexes, of the swallowing apparatus. Finally, the oral feeding test is performed, which evaluates the oral and pharyngeal phases of swallowing. The examination performed in the neurologic patient is different from that performed in the patient submitted to ENT or maxillo-facial surgery.

[Adenocarcinoma following restorative proctocolectomy for ulcerative colitis: a case report and review of the literature]

Restorative proctocolectomy with ileal pouch-anal anastomosis has been accepted as the surgical treatment of choice for most patients with ulcerative colitis. The occurrence of adenocarcinoma arising near or into the ileal pouch is rare. Only 19 such cases have been reported so far. The authors report a case of a 67-year old male who developed an adenocarcinoma in the small rectal stump 12 years after a restorative proctocolectomy with double stapled ileal pouch-low rectal anastomosis for ulcerative colitis unresponsive to medical treatment. They, after a literature review, examine same steps of the procedure and emphasize the importance of regular and prolonged follow-up for all patients having restorative proctocolectomy for ulcerative colitis.

Does optical coherence tomography identify arterial healing after stenting? An in vivo comparison with histology, in a rabbit carotid model

OBJECTIVE

To verify whether optical coherence tomography (OCT) can accurately monitor the occurrence of arterial healing after stenting.

SETTING

Delayed stent endothelialisation may predispose to stent thrombosis. OCT is a high-resolution intravascular imaging technique that accurately identifies stent struts and arterial tissues.

DESIGN AND INTERVENTIONS

Eight New Zealand white rabbits underwent the implantation of single bare metal stents (diameter 2-2.5 mm, length 8-13 mm) in the right common carotid artery through the external carotid artery. After a median of 11 days (range 2-28), the stented arteries were visualised by OCT, with images acquired at a pull-back speed of 0.5 mm/sec. The rabbits were then euthanised, vessels were formalin-fixed and finally processed for histopathology.

RESULTS

We analysed 32 cross-sections from eight stented carotid arteries, for a total of 384 stent struts. OCT detected all of the stent struts in 30 of 32 cross-sections (93.7%), and correctly identified the presence/absence of tissue for every strut. Histological and OCT measurements of mean neointima thickness (0.135 (SD 0.079) mm and 0.145 (SD 0.085) mm, respectively, p = NS) were similar and closely related (r = 0.85, p<0.001). Neointima area progressively increased with longer time intervals from stent deployment to sacrifice; histological and OCT measurements were similar for each time interval. The intra-observer and interobserver reproducibility of OCT neointima measurements were excellent (R2 = 0.90 and 0.88, respectively).

CONCLUSIONS

OCT is a promising means for monitoring stent strut coverage and vessel wall healing in vivo, the relevance of which will become even more significant with the increasing use of drug-eluting stents.

[Adenocarcinoma of the appendix. A case report and review of the literature]

Primary adenocarcinoma of the appendix is a rare malignancy that constitutes less than 0.5% of all gastrointestinal neoplasms. Usually the diagnosis is made only after histological examination of surgically removed inflamed appendix. Alternatively represent an unexpected finding, confirmed by frozen section, during surgery performed for acute appendicitis or other non appendiceal pathologies. Natural history is strongly influenced by anatomic peculiarities of the appendix that predispose to early spread and perforation. Frequently is associated with synchronous and metachronous colorectal or extraintestinal cancers. The correct management is the right hemicolectomy as a primary procedure in the case of preoperatively or intraoperatively diagnosis or as secondary procedure, after two-three weeks from appendectomy, when the microscopic examination of specimen reveals the presence of adenocarcinoma. Right hemicolectomy is the best treatment for all histologic types (colonic, mucinous, adenocarcinoid), in presence of perforation and even in Dukes A tumors. A careful intraoperative search for synchronous lesions and a life-long program of surveillance for the detection of early stage metachronous carcinomas are recommended. The Authors report a case of primary adenocarcinoma of the appendix occurred in a 78 year-old female patient, diagnosed incidentally during surgery performed for ileus from suspected cecal neoplasm.

[Parathyroid carcinoma: clinical case and review of the literature]

INTRODUCTION

Parathyroid carcinoma is a rare endocrine neoplasm, difficult to define clinically and histopathologically.

CASE REPORT

The case concerns of a 20 years old male with situs viscerum inversus (with dextrocardia), and symptoms: asthenia, oliguresis, nausea, emesis, myalgia, lower limb paresthesia and very high levels of calcium and PTH. Laboratory findings (PTH 580 pg/ml; Ca 12.40 mg/dl; P 1.9 mg/dl), echography, TC, and parathyroid scintigraphy, associated with clinical data, have suggested hypothesis of parathyroid carcinoma confirmed by histological examination and immunochemistry. Surgery was efficacious with normalization of Calcium and PTH levels, and disappearance of symptoms. After two years no signs of local recurrence were present, but imaging show pulmonary micronodulations of uncertain pathological meaning.

DISCUSSION AND CONCLUSION

No clinical or bio-humoral data allows a preoperative diagnosis of parathyroid carcinoma. Only with definitive pathology and immunohistochemistry it is possible to differentiate an adenoma from a carcinoma. Surgery is the only effective therapy and therefore should be always performed. This neoplasm usually relapses, locally first and later with distant metastases. For this reason after surgery the patients should always undergo a strict follow-up programme including evaluation of PTH and calcemia.

[Complicated diverticular disease. Three cases of colovesical fistulas and review of literature]

Colovesical fistulas represent a possible less frequent complication of diverticular disease of colon. They represent a complex condition because of the possible and unexpected evolution into a septic shock with a high risk of death. The Authors report three cases of colovesical fistula as a complication of diverticular disease. They underline the importance of early diagnosis, specific antibiotic therapy and appropriate surgical therapy realized in one or two stages according to general and local conditions of each patient.

[Mininvasive treatment of strangulated paraesophageal hiatal hernia in emergency. Case report]

The Authors report a case of strangulated paraesophageal hiatal hernia occurred in a elderly woman and treated with laparoscopic approach. After review of the literature regard on this uncommon pathology that present about 5% of the hiatal hernias, they emphasize that the laparoscopic approach is appropriated even in emergency and comprises complete reduction of the stomach in abdomen, control of suitable position of the distal esophagus and cardias and making of effective hiatus-plasty.

Presence of membrane and soluble forms of Fas ligand and of matrilysin (MMP-7) activity in normal and abnormal human semen

BACKGROUND

The aim of this study is to shed some light on the role of the Fas system in human semen, by investigating whether there is an association between the expression of the molecules regulating the Fas system [membrane-bound Fas ligand (mFasL), soluble Fas ligand (sFasL) and matrilysin, the metalloprotease cleaving mFasL to sFasL] and sperm parameters.

METHODS

We investigated, by flow cytometric analysis, the presence of FasL on spermatozoa from normozoospermic and teratozoospermic subjects and, by western blot, the presence of sFasL and matrilysin in the seminal plasma of the same samples as well as on samples from azoospermic subjects. The enzymatic activity of matrilysin was examined by gel zymography.

RESULTS

We observed that sperm cells expressed mFasL in 22% of normozoospermic men, whereas it was absent from spermatozoa from teratozoospermic patients. Higher levels of sFasL and augmented enzymatic activity of matrilysin were found in azoospermic samples.

CONCLUSIONS

The presence of mFasL on sperm from normozoospermic men and its absence in pathological samples emphasize the role of the Fas system in human semen. Moreover, the presence of both sFasL and matrilysin in seminal plasma implies a fine regulation of the function of the Fas system and, consequently, of the apoptotic process in the human genital tract.

An amperometric glucose biosensor prototype fabricated by thermal inkjet printing

The prototype of an amperometric glucose biosensor was realized by thermal inkjet printing using biological and electronic water-based inks, containing a glucose oxidase (GOD) from Aspergillus niger and the conducting polymer blend poly(3,4-ethylenedioxythiophene/polystyrene sulfonic acid) (PEDOT/PSS), respectively. The biosensor was fabricated microdepositing PEDOT/PSS and GOD, in sequence, on ITO-glass, by a commercial inkjet printer, with the help of a commercial software. High density microdots matrices were so-realized, with a calculated resolution of about 221 x 221 dpi (dot per inch). By means of a rapid and easy assay it was demonstrated that no activity loss occurred upon the printing of GOD, despite of the use of a thermal printhead. The device was encapsulated in a semipermeable membrane of cellulose acetate, applied by dip-coating, in order to prevent dissolution of the enzyme and/or PEDOT/PSS in water. The preliminary response of the electrode was measured in an aqueous glucose solution in the presence of ferrocenemethanol (FeMeOH) as a mediator, and resulted linear up to 60 mM in glucose. The best sensitivity value achieved was 6.43 microAM(-1) cm(-2) (447 nAM(-1) U(-1) cm(-2)). The characteristics of the device, and the possible performance improvements have been analyzed and discussed. The reported findings indicate that inkjet printing could be a viable instrument for the easy construction of a working biosensor via direct digital design using biological and conductive polymer based inks. Such an approach may be seen as an example of "biopolytronics".

Peritoneal mesothelioma in a case of inguinal hernia. A review of the literature

The peritoneal mesothelioma (PM) is a rare, benign or malignant, primary tumour, arising from the peritoneal membrane. The most frequent histological form is the malignant one with an incidence of 2-2.6 new cases per million per year. The symptomatology is insidious and poses difficult problems in the diagnosis and the treatment. Instrumental diagnostic investigations are useful only in the diagnostic orientation. Only the pathologic examination allows to distinguish a peritoneal carcinomatosis from PM. The prognosis of MPM is pour. An intense multimodal therapy, combining surgery with CT and RT, increases the survival rates in the patients with MPM. It has been proposed that hernia of abdominal wall play a role in the pathogenesis of this tumor. We believe that hypothesis seems unlikely considering the enormous discrepancy between the incidence of hernial pathology and PM.

[Collaborative study on peritoneal dialysis (PD) as first dialysis treatment in an Italian region: 1994-2000]

BACKGROUND

In Lazio, only about 5% of uremic patients are on peritoneal dialysis (PD). The present study focuses on the parameters of PD selection, the treatment schedules, and the clinical outcomes of PD patients in the nine public facilities offering a PD program. A cohort of 249 first-time PD patients, from July 1, 1994 to December 31, 2000, was retrospectively considered.

METHODS

For the enrollment of the patients, the Regional Dialysis Registry databank was consulted. On December 31, 2000, a systematic review of patient charts was performed to extract the reasons for the PD choice, details of PD schedule, peritonitis episodes, reasons for drop-out, and patient survival rates. In regard to technique success-defined as the probability of having a patient alive on PD-change of modality and death were considered as final events. In regard to patient survival, only death, even in the first 2 months after a shift to hemodialysis, was considered the end point.

RESULT

The main PD selection reasons were patient and/or nephrologist preference in 90% of cases. One-hundred eighty-nine patients (76%) had been started on CAPD. During the follow-up, 38.2% dialysis schedules had been modified at least once. At the end of follow-up, 41.2% patients were on APD. The peritonitis rate was one episode per 30 patient-months (1 per 27 patient-months in CAPD; 1 per 37 patient-months in APD; p = 0.08). The technique success rate was 66.3% after 2 years and 49.8% after 3 years. The patient survival rate was 81.1% after 2 years and 68.7% after 3 years.

CONCLUSIONS

Patients chose PD as a first dialysis treatment mainly because of reasons unrelated to their clinical status. The technique's success, patient mortality rates, and the peritonitis rate do not explain the low PD diffusion in the region. The peritonitis rate meets the target criteria for excellence recommended by the Italian Society of Nephrology. The observed outcomes may have been favored by the selection of motivated patients and by the increased use of APD.

FLIP is expressed in mouse testis and protects germ cells from apoptosis

Apoptosis control in adult testis is crucial to achieve normal spermatogenesis. In this study c-FLIP, an apoptosis-modulating protein, was investigated. In Western blot and immunohistochemical analyses, the 55 KDa c-FLIP long isoform (c-FLIP(L)) was found to be expressed strongly in spermatocytes and spermatids, at low levels in spermatogonia and at almost undetectable levels in Sertoli cells. This expression pattern was confirmed by Northern blot analyses. Further experiments carried out on GC-1spg germ cell line revealed that reducing c-FLIP(L) expression increases Fas-dependent apoptosis. Conversely, restoring c-FLIP(L) expression reduces this response to control levels. Caspase-10 expression was found to match c-FLIP(L) expression pattern; further, caspase-10 activation upon anti-Fas treatment inversely correlated with c-FLIP(L) expression. Finally, TUNEL staining of seminiferous tubules incubated with anti-Fas antibody showed that apoptosis occurs mostly in basally located germ cells, indicating that such cells, expressing low levels of c-FLIP(L), are sensitive to Fas-mediated apoptosis. These data indicate for the first time that c-FLIP(L) might control germ cell apoptosis and caspase activity in the adult testis.